ECONOMICAL GEOLOGY OF ILLINOIS. REPRINTED FROM THE ORIGINAL REPORTS OF THE GEOLOGICAL SURVEY, WITH ADDITIONS AND EMENDATIONS BY A. H. WORTHEN, STATE GEOLOGIST. VOLUME 3. 1882. H. W. KOKKEB, STATE PBINTEB AND BINDER, SPRINGFIELD, ILL . TABLE OF CONTENTS. CHAPTER I. GEOLOGY OF NORTHWESTERN ILLINOIS. Pag6S. By James Shaw 1 to 20 CHAPTER II. GEOLOGY OF JODAVIESS COUNTY. By James Shaw 20-54 CHAPTER III. GEOLOGY OF STEPHENSON COUNTY. By James Shaw , 54-73 CHAPTER IV. GEOLOGY OF CARROLL COUNTY. By James Shaw 73 80 CHAPTER V. GEOLOGY OF WINNEBAGO COUNTY. By James Shaw 80-94 CHAPTER VI. GEOLOGY OF BOONE COUNTY. By James Shaw 94-104 CHAPTER VII. GEOLOGY OF OGLE COUNTY. By James Shaw... .. 104-125 278932 IV TABLE OF CONTENTS. CHAPTER VIII. GEOLOGY OF LEE COUNTY. Pages. By James Shaw 125-142 CHAPTER IX. GEOLOGY OF WHITKSIDE COUNTY. By James Shaw 142-172 CHAPTER X. GEOLOGY OF BUREAU COUNTY. By James Shaw 172-192 CHAPTER XI. GEOLOGY OF HENKY COUNTY. By James Shaw 192-210 C H A P.T E R XII. GEOLOGY OF MARSHALL AND PUTNAM COUNTIES. By James Shaw 210-226 CHAPTER XIII. GEOLOGY OF BOCK ISLAND COUNTY. By A. H. Worthen and James Shaw 226-246 CHAPTER XIV. GEOLOGY OF PEORIA COUNTY. By A. H. Worthen . 246-265 CHAPTER XV. GEOLOGY OF MCDONOUGH COUNTY. By A. H. Worthen 265-279 CHAPTER XVI. GEOLOGY OF MONROE COUNTY. By A. H. Worthen... .. 279-300 TABLE OF CONTENTS. CHAPTEE XVII. GEOLOGY OF MACOUPIN COUNTY. PagCS. By A. H. Worthen 300-322 CHAPTER XVIII. GEOLOGY OF SANGAMON COUNTY. By A. H. Worthen 322-337 CHAPTER XIX. GEOLOGY OF CLABK COUNTY. By A. H. Worthen -. 337-352 CHAPTER XX. GEOLOGY OF CRAWFORD AND JASPER COUNTIES. By A. H. Worthen 352-368 CHAPTER XXI. GEOLOGY OF LAWRENCE AND RICHLAND COUNTIES. By A. H, Worthen 368-383 CHAPTER XXII. GEOLOGY OF WABASH AND EDWARDS COUNTIES. By A. H. Worthen... .. 383-399 CHAPTER XXIII. GEOLOGY OF WHITE AND HAMILTON COUNTIES. By A. H. Worthen. . . . . 399-416 CHAPTER XXIV. GEOLOGY OF WAYNE AND CLAY COUNTIES. By A. H. Worthen... .. 416-434 CHAPTER XXV. GEOLOGY OF CUMBERLAND, COLES AND DOUGLAS COUNTIES. By A. H. Worthen. . . . . 434-449 VI TABLE OF CONTENTS. CHAPTER XXVI. GEOLOGY OF WILLIAMSON AND FBANKLIN COUNTIES. Pages. By A. H. Worthen 449-467 CHAPTER XXVII. GEOLOGY OF BOND COUNTY. By G. C. Broadhead : 467-475 CHAPTER XXVIII. GEOLOGY OF FAYETTE COUNTY. ByG. C. Broadhead .' 475-490 CHAPTER XXIX. GEOLOGY OF MONTGOMERY COUNTY. By G. C. Broadhead 490-498 CHAPTER XXX. GEOLOGY OF CHEISTIAN COUNTY. ByG. C. Broadhead 498-506 CHAPTER XXXI. GEOLOGY OF SHELBY COUNTY. By G. C. Broadhead 506-519 CHAPTER XXXII. GE LOGY OF EFFING [I AM COUNTY. By G. C. Broadhead 519-530 CHAPTER XXXIII. GEOLOGY OF MOULTEIE, MACON AND PIATT C 3UNTIES. By G. C. Broadhead j>30-544 CHAPTER XXXIV. GEOLOGY OF GALLATIN COUNTY. By E. T. Cox.. ..544-569 TABLE OF CONTENTS. VII CHAPTER XXXV. < GEOLOGY OF SALINE COUNTY. Pages. By E. T. Cox 569-586 CHAPTER XXXVI. GEOLOGY OF LIVINGSTON COUNTY. By H. C. Freeman .. 586-596 CHAPTER I. GEOLOGY OF NORTHWESTERN ILLINOIS. That part of the State of Illinois embracing the valley of Eock river, and thence north and west of the same, and more minutely described in the following detailed county reports, is, geologically, agriculturally, ^and in a manufacturing point of view, one of the most interesting portions of our great State. The valley of Rock river, if indeed the high rolling prairie on either side can be called a valley, in fertility and beauty of prairie land is perhaps unequalled in the West. The river itself swift flowing, broad, clear as crystal affords one of the most magnificent water powers in the world. At Camden, Sterling, Dixon, Grand DeTour, Oregon, Rockford, Rockton and Beloit, excellent dams are already built and extensively used for milling and manufacturing purposes. Others will be built in due course of time. Almost every half dozen miles contains one or more of these heavy water powers. At one end of the stream are the lumber regions of Wisconsin; at the other, the coal fields of Rock Island. On either side is the richest agricultural region in the State. Along the banks and in the bed of the river are many kinds of stone from the best Silurian formations. A railroad up the val- ley, joining the coal and lumber, will be built at no distant day. In addition to this, the Government survey of Rock river, made under charge of General WILSON, and submitted in the form of a report to the War Department some four years ago, shows that the improvement of Rock river navigation by slackwater dams from Eock Island to Lake Horicon, thence across to Lake Winnebago, and thence down Fox river in Wisconsin to Lake Michigan, is not only a feasible project, but is full of interest to the people of this valley and to the whole Northwest. It will thus be seen that Rock river and its valley, in their present and prospective resources, salubrity of climate and beauty of location, have not their equal in the State, - Z ECONOMICAL GEOLOGY OF ILLINOIS. or perhaps in the Nation. The geological formations along this stream are also of an interesting character. The section of the river bluffs herewith presented, and the following county reports, contain detailed descriptions of these formations. At Beloit and Eockton the dull, yellowish, earth-colored, buff lime- stone, with its bands of dark-blue, is the surface rock ; half way to Eockford this formation sinks below the upper division of the Tren- ton; three miles above Eockford, and at the city, the warm cream- colored Galena limestone outcrops in the river bluffs to the height of one hundred feet; lower down the Galena gradually thins out, until the buff again conies to the surface in a low axis at Byron. From Oregon to Grand DeTour the castellated hills of the St. Peters sandstone, shining white, brown, and name-colored in the sunlight, and rising to an elevation of nearly two hundred feet, form striking and picturesque objects in the landscape ; below these the solid lower Magnesian limestone probably forms the floor of the glancing river. At Dixon two divisions of the Trenton may be examined almost side by side for some distance; at Sterling the green and blue shales of the Cincinnati group, and the chert-banded and den- drite-speckled Niagara limestone outcrop heavily in the same quarry; from Sterling to Erie, and even lower down, the Niagara continued in the bed of the river and in its banks, a low outcrop, changing before it runs under the Coal Measures into a softer, whiter, finer- grained stone, formerly called the LeClaire limestone ; from a few miles below Brie to Camden, the gently rounded hills and black limestones of the productive Coal Measures rise to varying eleva- tions ; from Camden to the Mississippi the river rushes over a smooth floor of solid, dove-colored Hamilton limestone of Devonian age. That part of the State between Eock river and the Mississippi, except JoDaviess and a part of Carroll counties, is mostly high, rolling prairie land, dotted with beautiful groves of timber, and abounding in many small streams, which afford good mill seats and light water powers. The soil is dryer than the flat prairies of Cen- tral Illinois. The portion above excepted, being within the productive lead basin, is more abrupt and broken. The agricultural and horticultural productions, kinds of timber, mineral wealth, superficial extent of geological formations, soils and their capabilities and adaptations, and other matters of scientific and economical interest, will be found set out in detail in the county reports following this article, but need not be again repeated in this place. PRELIMINARY CHAPTER. 6 The Mississippi river on the west exposes a fine section of its rocks from Dunleith to Rock Island. At the latter place the Ham- ilton limestones and Coal Measures both outcrop and are the pre- vailing rocks as far up as Moline ; from thence to the south line of Carroll county massive walls of Niagara limestone in places appear like vast mural escarpments, bounding the broad Mississippi bottoms on the east ; about Bluffville the Cincinnati shales and clayey lime- stones are the predominating ..rocks ; at Savanna the same Cincin- nati group is capped with more than a hundred feet of coarse, reddish-brown Niagara limestone ; and as we ascend towards the north line of the State, massive, solid Galena outcrops occur, the famous lead-producing rocks of the Northwest. Leaving these rocky formations for the present, it may be well to discuss some questions connected with the superficial deposits cov- ering them. If all the soils, clays, sands, and gravels, and other loose mate- rials spread over the face of the country were removed, the proba- bility is that the rocky surface thus displayed would present valleys of erosion and elevated ridges ; but these inequalities would not per- haps be greater than those now appearing on the surface. The glacial Drift period, and the tremendous forces acting through it, are not well understood by geologists, but they had much to do with the deposition and present arrangement of loose materials, covering the rocks concealed beneath them. Clays, sands, and various mixtures, are originally derived from the decomposition of the primitive rocks. The silent processes of nature, to-day, as in past geological time, are grinding rocks into clays and sands, and re-cementing clays and sands into rocks. The affinities of rocky matter can be destroyed by atmospheric and chemical agencies, but the elements will still remain. There are two theories as to the deposition of the loose materials covering the rocks in this part of the State. One is, that they are derived from the slow decay of the underlying rocks, leaving the clay in situ, in the exact places where the rocks rotted away. The other is, that the drift forces mingled, mixed, and deposited these loose materials, having gathered them from long distances, and from many and widely separated sources. In the part of the State now under consideration, evidences of the truth of both these theories can readily be found. In the pro- ductive lead region it is now conceded that the drift forces did not act at all or acted in a modified form. The productive lead rocks are covered by a peculiar reddish clay, derived in a large part, I 4 ECONOMICAL GEOLOGY OF ILLINOIS. think, from the decay of the upper strata of the rocks. It bears little evidences of mixing or transporting agencies. The top is enriched by vegetable and atmospheric influences, and has become a thin, poor soil. As it is penetrated, it becomes a reddish clay ; pieces of float mineral are found, sometimes in considerable quantities, and before the solid strata are found, apparently lying in situ, unworn by water, and becoming more numerous, until the solid rock is reached, as if they were harder fragments of the original rocks, which have withstood the general decay of the mass. Fragmentary patches of the lead region are undoubtedly driftless regions, but in many places the drift has invaded the lead regions. In the northwestern portions of Carroll county, where the indica- tions are strong that the soils and clay are derived from the decom- position of the underlying rocks, fragmentary boulders are often found on the surface of the ground and in the ravines, showing, as it seems, that even these driftless lead regions have been submerged, perhaps many times, since their uplift from the Silurian seas. The finely comminuted, greenish and creamy yellow colored clays, forming the subsoil over small extents of Northwestern Illinois un- derlaid by the Cincinnati shales, would seem to indicate an origin from the decomposition of the earthy shales below. But in many places and over large extents of this part of the State, the transportation of soils and clays, and a universal mingling and mixing of the surface materials of the earth, is a fact patent to the most casual observer. The gravel hills of Ogle county, and the long gravel beds of Winnebago and Boone counties, mingled with white sand; the stratified and partially stratified clays and sands to be met with almost everywhere; the boulders scattered over the prairies all owe their present arrangement to the Drift forces. Over these places the underlying rocks are hidden by the concealing Drift. Laminated clays cover the indurated rocks. These clays are in some cases nothing but the sediments and precipitates of peaceful, shallow seas ; but the boulder and gravel beds indicate mightier forces and belong to the true glacial Drift. That vast glaciers of ice once extended over large portions of North America is now universally conceded. Their slow, crawling motion and irre- sistible force ground the rocks to powder, as wheat is ground to flour between the upper and nether millstones ; not only ground them to powder, but rounded and polished the boulders and the gravel, planed and grooved the rocky surface of the earth, and moved the vast masses of Drift materials from place to place in a slow procession. Direct evidences of the ice forces of the glacial PKELIMINARY CHAPTER. 5 period are not met with so frequently, as a modified form of these forces. Along the ridges and gravel hills north of Foreston, in Ogle county, the great accumulation of gravel, sand and boulders pre- sents the appearance of glacial moraines, as if two glaciers had met and deposited their accumulated loads of dirt, sand, gravel and boulders, much of which seems to have been torn from rocky for- mations of the Silurian age, at no great distance from the place of final deposit. But the great mixing and transporting agency which arranged, assorted and deposited most of our Northern Illinois Drift deposits, was evidently the mixed action of ice and water. When the temperature of the glacial winter began to grow warmer, and the great moving fields of ice began to melt, streams of turbid water would rush out and form shallow seas and lakes. The glaciers on the more elevated portions of the land, still fed by perpetual snows, would creep into the neighboring bodies of water, break off and float away in the form of icebergs and floes, bearing with them the boulders, gravel and dirt, torn from the hills and outcropping rocks along their passage. As this floating ice melted, either by an in- crease of the earth's temperature, or by being borne into a warmer atmosphere further south, the materials with which it was freighted would sink to the bottom, and become subject to the action of a new force, the assorting and transporting force of currents of flow- ing water. The contraction and expansion of the ice over these shallow lakes or seas, caused by alternate freezing and thawing, also exerted a powerful influence in tearing loose stones from the neighboring banks and piling them into long heaps and gravel beds. In some of the lakes in Northwestern Iowa the frost power is pro- ducing wonderful phenomena, giving rise to the popular error of walled lakes. Thus it will be seen that the first and greatest of the Drift forces was the glacier; then the floating iceberg and ice field produced their results, carrying the large boulders from place to place, and dropping them over the ice cold seas; and last the wave and cur- rent forces of water, after the ice had in part, or altogether melted, left the loose clays, sands and subsoils substantially as we find them now. Arctic travelers have made us somewhat familiar with the deso- lations and savage beauty of the North polar regions home of the ice- bergs, land of the glaciers, and realm of enduring frost. The phenomena there witnessed at the present day are exactly similar to the ancient forces acting over these prairies, as I have above attempted to describe them, except in so far as they were modified 6 ECONOMICAL GEOLOGY OF ILLINOIS. by the leveler nature of this country as compared with snow-bound, ice-locked Greenland. The icebergs rise cathedral and sphinx-like from the bosom of the fiords and inland seas, making an ice forest in places over the watery wastes. They impinge upon each other with the crash of parks of artillery, and float away on gulf streams and melt in warmer latitudes, strewing the floor of the ocean with their adher- ing earth and stones. The blaze of the Arctic summer sun lights them up into brilliant colors. Peaks of flame, columns of emerald, sapphire and blue, move slowly over the gieen waters, and the play of prismatic colors is indeed beautiful in all the reflected and re- fracted, changes of .the bergs. Glaciers are creeping slowly down from the neighboring mountains ; fed at their upper ends with per- petual snows; their lower ends constantly breaking off in the waters, and sending away fields of ice and icebergs, loaded with the debris and stones collected in the downward journey. Similar phenomena, perhaps in a modified form, were once dis- played over all the regions traversed by the Drift. The ice gradually melted away, commencing south and disappearing up to the Arctic regions. In process of time the waters gave place to the dry land, and our northern prairies remain, moulded into gentle undulations by the process of the retiring waves. The startling theory of the Ice Period in North America, announced by Professor AGASSIZ in the "Atlantic Monthly" for July, 1864, at that time was almost too much for the faith or credulity of scientific men. Now, a large portion of the scientific world accepts the theory then announced. In his recent expedition to Brazil and up the Ama- zon, the traces of a great glacier, filling the whole valley of that large river, were discovered. When such a sea of ice existed under the very tropic skies, this world must indeed have been in the midst of a glacial winter, where snows, and frost, and ice, held supreme sway. We wonder if, then, the progenitors of the mound-builders and ancient copper-miners and workers built their snow and ice huts, and moved about in their light kiyaks, as the Esquimaux of to-day do in frigid Greenland ! The influence of these glacial drift-forces upon soils is worthy of a passing thought. They changed the surface of the earth from its conditions during the Carboniferous ages, and made soils, by the processes above enumerated, fit to produce grasses, grains, fruits, and hard-wood trees. They prepared the earth for civilized man. In this part of the State, in attempting to classify soils and earths thus mingled and made, there is no end to the distinctions and PRELIMINARY CHAPTER. V classifications. Soils are light or heavy, warm or cold, dry or wet, compact or porous, fine or coarse, hungry, leachy, loamy, sour, sweet, clayey, sandy, limey, marshy, peaty, and various combinations of these, too numerous to mention. Silica, or the earth of flints, alumina, lime, magnesia, potash, and various salts and metalloid compounds, unite in chemical or mechanical combinations to make up these soils. The humus, or geine, which gives richness and fat- ness to the land and blackness of color, is chiefly derived from suc- cessive growths and decays of grasses and other vegetation. The productiveness of these soils depends not alone on the nature of the soils themselves, but also upon climatic and atmospheric influences, and the nature and properties of the subsoils and under- lying drift materials. If the subsoil is gravelly, marly, leachy or porous, so as not to retain too much moisture, fruits and cereals will flourish. If a hard-pan or impervious clay lies under the soil, so as to retain the surplus moisture, corn and grasses will perhaps do better. The practical agriculturist will knock the bottom out of such a soil if he can, by deep plowing or underdraining, so as to let the surplus water leak out, and permit the sunbeams and kiss- ing winds to penetrate and sweeten the land. Not only the agriculturist, but the horticulturist may learn a les- son from this. In the first place, let him select one of nature's orchard spots, if that be possible, on which to plant his trees and vines. A light soil, porous subsoil, sheltered, sunny exposure, and well-drained slope or hillside, is the favored spot. Then let him plant, in proper season, of the best and hardiest varieties, in holes big as little cellars. Take care of the young trees, feed them with fertilizers and good cultivation, wage war with their insect foes, and in due time an abundant fruitage, even in this climate, will be the result. If nature has not given him an orchard site, then he must make one. Do artificially what nature has failed to do. Drain and under- drain, plow and subsoil plow, manure and feed with fertilizers, plant shelter-belts to modify and sift the blistering winds, and in this way an orchard or vineyard may be made to grow, whose generous fruit- age will more than repay the expense and toil. But, leaving these topics, which belong rather to practical agriculture and horticulture than to geology, I pass to notice some phenomena more particularly discernible along the small streams between the Mis- sissippi and Rock rivers. There are a number of these large creeks and small rivers, referred to in the county reports. Those crossing the face of the country in an eastern or western direction generally * ECONOMICAL GEOLOGY OF ILLINOIS. have the strata along the north side of the stream elevated higher than those on the south side. In some instances the stream is the dividing line between an older and more recent formation. The Cin- cinnati shales and limestones often underlie the level prairies on the south side, up to the very water's edge ; while the country on the north side rises in rather bold outcrops of the Galena limestone. I think the streams are oftener than otherwise the dividing line be- tween different groups and formations. Closely connected with this phenomenon is another. The streams often seem to flow in fissures or cracks of the underlying rocks. Slow upheavals, and slight contractions in the cooling earth perhaps, made these fissures. In time they filled partially, making the nar- row bottoms and the beds of the present streams. Slight faults were thus left, which seem to be bounded by the streams, and fully account for the difference of elevation on different sides of east and west streams. While speaking of the surface geology of the region between the two rivers, a few words as to the origin and formation of the prai- ries may not be out of place. The largest portion of this part of the State is prairie land. In it all kinds of prairies may be seen such as the high, upland prai- ries, the river bottoms or alluvial prairies, and the low, wet swamp lands. There is quite a diversity of opinion as to the origin and forma- tion of these treeless and grass-covered regions of the Northwest. One theory attributes them to annual fires sweeping through the grass, and killing every tree, germ and young tree, almost before they could take root. In some places the fires are supposed to have encroached year by year upon the forests ; in other places, as, for instance, along the streams, in the deep hollows, or in wet places, where the fires would be checked, the timber would spring up and displace the prairies. Another theory accounts for the treeless char- acter of these plains from the lacustrine origin and nature of the prairie soils and subsoils. Trees will not naturally grow in this sedimentary, finely comminuted prairie soil, according to this theory. Others attempt to explain prairie phenomena by atmospheric and climatic influences, marking out certain zones of moisture and dry- ness. They bound forests and prairies by qertain isothermal lines. Another theory, advocated with force and plausibility by Professor LESQTJEKEUX, in the first volume, page 187 et seq., finds all our prai- ries to originate from causes similar to those which form peat-beds, and are in fact incipient peat-beds, drained before completed. In PRELIMINARY CHAPTER. 9 his own clear language, he finds "that all the prairies of the Mis- sissippi valley have been formed by the slow recession of sheets of water of various extent, first transformed into swamps, and by- and-by drained and dried. The high, rolling prairies, the prairies around the lakes, those of the bottoms along the rivers, are all the result of the same causes, and form a whole in an individual sys- tem." No one of these theories is sufficient to explain all the phenomena noticed in making an examination of the prairies. As in most such cases in theoretical geology, all of them perhaps contain some truth, and may be applicable to localities more or less extended. The burning of the forests, in a few cases doubtless, has changed timber into prairie land, and prevented the timber from, invading, small tracts of the prairies. But the sweeping, consuming autumnal prairie fires are not sufficient to account for the origin of our wide prairies, else prairies would be found scattered through all the tim- bered regions of the continent. Neither is atmospheric causes suffi- cient, for the observations of meteorologists show the annual pre- cipitation of moisture in the form of rains, over our northwestern prairies, quite as evenly and extensively as in the timbered regions of the eastern and northern parts of the continent. The chief causes of the treeless character of our prairies are undoubtedly found in the soil itself. It is very true that trees, even those whose native habitats seem to be the damp alluvial soils of our river banks, will flourish and grow when planted upon the prairies ; but the artificial process of planting seems to fit the soil for their reception. Even vines, In- dian corn, and many other sorts of vegetation, will flourish when thus artificially planted, but never would grow naturally and of their own accord upon the grass-bound prairie sod. The prairie soil is naturally adapted to the growth of prairie grasses ; and the prairie grasses not only resist the growth of trees, but actually kill them out. By destroying the grasses and sods and cultivating the trees, they will grow vigorously. The prairie soil has certain anti- septic properties, and ulmic and other acids, which give it a sour- ness. The prairie grasses naturally flourish in such a soil. These properties in the soil, and these grasses, are all unfavorable to the growth of trees; and it is only when their influences are counter- acted by cultivation or other local causes, that trees will grow in health and vigor. Cultivation does destroy this sourness in the soil ; and I believe if all the cultivated prairies of the State were suffered to relapse into uncultivated wastes, instead of going back to their 10 ECONOMICAL GEOLOGY OF ILLINOIS. prairie condition, they would become eventually covered with bram- bles, thickets and growths of timber. In this part of the State, along the Mississippi, Eock river, and other streams, much of the alluvial bottom subject to annual over- flow, is covered with timber. There are, however, alluvial prairies along these streams, timberless, and for the most part sandy and coarse-grained, and entirely different in composition and texture from the usual Illinois upland prairies. The swamp lands of Whiteside, Lee and Carroll counties afford a fine illustration of Professor LESQUEKEUX'S theory of the gradual transformation of swampy, boggy ponds, marshes and swales, into the black, spongy moulds of our richest prairies. Aquatic vegetation,' the gradual encroachment of the land into ponds, the slow drying of our wet lands, and the gradual filling up of the ponds by suc- cessive growths and decays of aquatic vegetation, is building up, rapidly, sour-soiled, treeless prairies. The processes are similar to those forming the peat beds. The results of the processes are cur- tailed and modified, and a peaty-soiled prairie is formed, instead of a bog or bed of peat. But the high, rolling prairies of Carroll, Stephenson, Winnebago, and parts of Ogle and Whiteside counties, with, in many instances, but thin soils covering the coarser drift materials below, do not show so plainly the same sort of originating causes. They are in- terspersed with numerous small groves of timber. These grow along the alluvial mixed soil of the streams, and upon the ridges and patches thrown up and beat together by the waves and currents of the broad lake-like expanse of water, which covered this part of the State immediately subsequent to the glacial Ice period. A few of these drift ridges, as in northwestern Ogle county, are treeless, owing perhaps to fires, or other local causes. Excessive humidity of these high, rolling, somewhat sandy prairies does not exist, and cannot satisfactorily account for their treeless character. Neither do they bear in their soils and subsoils the evidences of having once been swampy, marshy plains. When the waters of the broad shallow fresh-water sea, once ex- tending south and west of Lake Michigan, were slowly drained off, either by the breaking away of southern water barriers, or the slow upheaval of this whole region, parts of the bottom were undoubt- edly left as broad marshes, swales, and bogs, which assumed in due course of time a peaty character; but other parts must have been left comparatively dry, and covered with the fine, impalpable sedi- ment, constituting the basis of our present prairie soils. The swamp PRELIMINARY CHAPTER. 11 and peat lands of Lee, Whiteside and Carroll counties, afford fine examples of the former condition of things ; the rolling, dryer, sandier prairies of Stephenson, Winnebago, and parts of Carroll and Ogle counties, afford just as fine illustrations of the latter condition of things, while Boone county exhibits very plainly both. The treeless nature of the marshes is very satisfactorily accounted for upon Professor LESQUEREUX'S theory of the origin of the prairies. The treeless character of the high prairies must be accounted for by the nature of the soil itself; the natural tendency of an herb- aceous, rather than of an arboreal vegetation, to gain and keep possession of the prairie soil, aided perhaps by fires and other local causes. These views of mine may contain erroneous suggestions. I have had no special means to examine soils, or compare wide extents of prairie regions with each other. I arrive at my conclusions from simple observations of the prairies in this part of the State. I am satisfied that no one theory yet advanced, as to the origin and form- ation of the prairies, will account for all their phenomena, even in this limited portion of the State. Combined causes, operating with different degrees of force in different parts of the great prairie regions of the country sometimes one cause predominating, some- times another, and sometimes all together are more in harmony, it seems to me, with the effects left for our observation. Geological Formations. Leaving the surface geology and turning our attention to the rocky strata beneath, we find the following formations in descending order: The Niagara limestone, Cincinnati group, Galena limestone, Blue limestone, Buff limestone, St. Peters sandstone, and the upper surface of the Calciferous sandstone or lower Magnesian limestone. The Galena, Blue and Buff limestones are now classed as divisions of the Trenton limestone. The Calciferous sandstone can hardly be named among the exposed and outcropping formations of North- western Illinois. It is the floor of Eock river, at a point where the St. Peters sandstone outcrops in high bluffs along the shores of that stream. The local outcrops, superficial extent, characteristic fossils, and weathered appearances and exposures, are referred to in detail in the county reports, following. In this place I shall simply speak of their general characteristics and lithological appearances. The Niagara Limestone. This is a heavily-bedded, dolomitic, mag- nesian limestone, without any appearance of shaly or arenaceous 12 ECONOMICAL GEOLOGY OF ILLINOIS. beds, so far as I have noticed. In color, it ranges from a grayish- white to a brown or brownish-red, often finely speckled with minute dendritic-looking spots. In texture it is soft and fine-grained, like the LeClaire limestone ; tough, and of a horn-stone texture, like the Cordova lime-burning quarries ; crumbling, coarse-grained and brec- ciated, like the quarries at Fulton City. And yet, with all this diversity, there is a similarity of structure and appearance which makes it difficult to mistake the Niagara limestone for any of the other formations. From the north part of Carroll county to Port Byron, in Rock Island county, it caps the river bluffs, presenting that splendid castellated brown-red appearance so familiar to travel- ers on the Upper Mississippi river. It reaches a maximum thickness of one hundred and seventy-five to two hundred feet. It caps the mounds further north, and is called "the Mound limestone" by PERCIVAL and other of the earlier geologists. By Dr. OWEN it was named "the Corraline and Pentamerus beds of the upper Magnesian limestone," referring, doubtless, to the prevailing fossils. The Pentamerus oblongus is met with in great abundance in its upper beds, and its corals are so numerous and finely preserved in the form of silicified casts as to show us that the Niagara seas were the coral-paved seas of the Silurian age. The Cincinnati Group. Next in the descending order comes that group of clayey, unctious, fine-grained shales, formerly called the Hudson river shales by most of our Western geologists, but now more appropriately named by our own State geologist. The upper parts of the quarries show thin-bedded stratifications, but towards the bottoms of the quarries the strata become thick-bedded and solid. The thin shales are light-yellow, buff or green colored, soft, sometimes unctious to the feel, often giving a creamy color to the water, as it trickles down .from the quarries, and crumbling and melting into clays when exposed to atmospheric influences. Some of the massive strata near the bottom of the formation are intensely hard and very blue. The maximum thickness of this formation reaches perhaps a hundred feet. Above Savanna the outcrop is eighty feet in thick- ness, and at Bluffville a like thickness is exposed ; and a well, thirty feet deep, near by, exposes to the bottom the shales and clays of this formation. In a few places the thin, cream-colored strata break into rhomboidal, diamond-shaped blocks of great regularity. In a few localities the shales are almost black, and have so much carbon in their composition as to burn with a bright flame, giving PRELIMINARY CHAPTER. 13 out considerable heat and resembling caimel coal. The flame re- sembles that of burning petroleum. The fossils are mostly Brachiopoda, and exist in great abundance in some of the strata. The stone, even the best of the hard blue, except in certain localities, is utterly unreliable as a building stone. It disintegrates and crumbles on exposure to atmospheric influences. On this account natural exposures are rare. In the high bluffs it often presents this appearance. The elevation is capped by the castel- lated Niagara; then comes a gentle grass-covered slope, succeeded by the rough outlined, underlying Galena limestone, with numerous springs flowing out near the base of the shales. This group is the upper division of the lower Silurian, the Niagara being the lower division of the upper Silurian. The Galena Limestone. This limestone, in lithological character and general appearance, closely resembles the Niagara. It presents the same bold, castellated appearance. The color is more uniform, being generally a light-creamy, warm color, with shades of ashy- yellow and dirty- white. The structure is more homogeneous and uniform, having generally a sort of crystalline or sub-crystalline appearance, except when the lower beds sometimes assume, in their passage into the underlying Blue, the characteristics of the latter. The upper beds sometimes have a crumbling, sandy nature. The stone is massive, thick-bedded, solid, and becomes more enduring as it seasons. Its rich warm color and enduring nature make it a desirable material for heavy masonry. The characteristic coral, the Receptaculites Oweni, "the sun-flower coral" or "lead fossil" of the miners, or "honeycomb" of the common quarryman, is known to almost every one. This is the famous "lead-bearing" limestone of the Galena lead basin. It is heavily developed over the whole lead region or lead basin of the Northwest, a basin occupying an area, according to Professor WHITNEY, of about 4,000 square miles, and comprising portions of the States of Iowa, Wisconsin and Illinois. It reaches a maximum thickness of two hundred and fifty or three hundred feet. It is unnecessary at this time to speak of its mineral treasures in the shape of rich deposits of lead ore found so abundantly in its caverns, crevices and decayed and superincumbent clays, as in the first volume of these Eeports this subject has already been discussed at some length. The Wisconsin and Iowa State Geological Reports both devote considerable space to the discussion of the causes of 14 ECONOMICAL GEOLOGY OF ILLINOIS. the deposit of lead, its modes of occurrence, and various other interesting thoughts and questions connected therewith. A brief reference to our present knowledge upon this interesting subject of inquiry is all that will be attempted at the present time. If deemed necessary, it will be more fully treated of in the report upon the geology of JoDaviess county. The origin of the lead and other minerals of this district is one of the vexed questions. At least four theories have been advanced and argued. These are as follows : 1. That the waters of the Silurian ocean held the minerals, or their salts, in solution. At the time of the deposition of the lead bearing rocks, or at least before the deposition of the next overlying formation, the mineral matter was precipitated, in the form of sul- phurets, in the crevices of the rocks. 2. The injection from below of the mineral matter in a melted state up through the crevices of the rocky mass. Many dykes, lodes and true mineral veins, thrown up by volcanic or other igneous agency, doubtless owe their origin to this source ; but it does not satisfactorily explain the origin of the Galena lead. 3. The theory of sublimation supposes the metal to have existed in hot vapor or steam. As this cooled, crystallization took place, and the mineral matter adhered to the sides of the fissures in the rocks, as frost crystallizes upon the window-panes. Craters of vol- canoes, flues of furnaces and bloomaries also furnish familiar examples. 4. Another theory supposes that electro-chemical action caused a segregation of minerals into crystals in the soil, as geodes are formed. The first of these theories is the most universally received, so far as the origin of lead and its associated minerals, in the Galena lead district, is concerned. The injection of melted matter from below into the fissures of the rocks accounts for the origin of many true mineral veins in a satisfactory manner; but in the lead region of the Northwest the vast bodies of unfissured sandstones and other unmetallic formations below the lead-bearing rocks, make it almost impossible to trace the lead to this source. Professor WHITNEY, who is perhaps our best authority upon the geology of the lead region and the modes of occurrence of its mineral deposits, in his articles in the Iowa, Illinois and Wisconsin Geological Reports, has well nigh settled the question in favor of the deposition of the ore in the crevices of the rocks by aqueous solution. He believes that the minerals were held in solution by the waters of the ocean, which PRELIMINAKY CHAPTER. 15 deposited the lead-bearing rocks, and afterwards precipitated or de- posited in the fissures, and that the development of life in the ocean produced chemical combinations in the sea water, which caused the precipitation of the sulphurets. In this way sulphurets alone were deposited, but the oxidized combinations of the sulphurets would form "the few other accidental minerals found among these sul- phurets. The surface arrangement and systems of parallelism of the veins or lodes of productive mineral is a subject of interest in the mining district. East and west veins usually carry the mineral. North and south veins are unproductive, except in a few instances, where the general rule seems to be reversed. In connection with this, it may be well to remark that Dr. WHITE, the State Geologist of Iowa, has just announced that there is a well marked physical difference be- tween the lead ore of the east and west, and north and south lodes : and also, that they have found in Iowa lead ore with small adher- ing crystals of native copper. Both these announcements are inter- esting discoveries. Lead occurs in the form of float mineral, sheet mineral, and crystallized masses in openings and caverns. The float mineral is found in the red clay overlaying the lead-bearing strata, and results from the decomposition of the upper part of the lead-bearing rock, permitting the mineral to settle down into the clays thus formed. The sheet mineral exists in the form of thin veins in the solid rocks. The crystallized masses are found adhering to the tops and sides of caverns, or buried in the debris at their bottoms. The granular and fibrous structure is almost wanting in this lead region; the crystal- line is the only structure generally noticed. The causes of the fissures in these lead rocks is supposed to have been slow upheavals in the lead basin in past geological ages, and the dynamical agencies operating by reaspn of the contractions and expansions of whole geological formations. The historic sketch of mining for lead, found in the published re- ports of the Illinois Geological Survey, although far more indefinite than we could desire, is perhaps as perfect as we can make it. Many facts and statistics have been lost ; many items of interest were never preserved at all. At the present time lead mining is in a tolerably flourishing con- dition. The amount of mineral raised is not so great as formerly, but the price is better. Two practical conclusions seem to have been arrived at as a re- sult of geological examinations in the lead region. First, that no 16 ECONOMICAL GEOLOGY OF ILLINOIS. system of deep mining will ever be generally adopted, simply because deep-buried bodies of mineral do not exist. Second, that a much better and cheaper way to prospect for lead is to drift into and across the veins by adit levels, instead of sinking vertical shafts. In speaking of the Galena limestone, I have thus been tempted to speak of the treasures lying away in its dark vaults. These vast bodies of metallic wealth have given an interest and a name to this interesting formation. The fortunes torn from its hidden fissures, and those yet to be torn from fissures more hidden still, will always, and in all time to come, dazzle the eye and mind, while the more modest merits the rich, warm cream color, its enduring qualities as a building material, the good lime easily burned from it are almost forgotten or overlooked. The Bine Limestone Next succeeding in the descending order comes the Blue limestone, or Trenton limestone proper, of the earlier Western geologists. It is now regarded as the middle division of the Trenton group, the Galena above and the Buff below both being now regarded as members of the Trenton. The upper strata are thin-bedded, and of an ashy-white or dirty-buff color. The lower strata or layers are thicker-bedded, and of an intense ultramarine- blue, when first quarried, but afterwards bleach out to a paler or whiter blue. The whole of this division has a more or less con- choidal or glassy fracture when broken ; some of the bluer strata are exceedingly conchoidal in their fracture, and have been characterized in the common speech, all over the lead mines, as the "glass-rock." The Blue limestone reaches a thickness in this part of the State of from forty-five to sixty feet. It makes an excellent, and, when properly dressed and mingled in its shades of color, a beautiful building material. The Union school building in the town of Polo, a very handsome and tasteful structure, is built of this Blue lime- stone. An excellent article of common lime may be burned from it. All around the lead region, and where the streams cut through the Galena limestone, the Blue limestone appears. It is one of the most fossiliferous deposits in this part of the State. -A large species of Orthoceras, sometimes six or eight inches in diameter, and eight or ten feet long, is often found. A large shell, in a fossil state, related to the Nautilus, perhaps the Lituites undatus of Hall, is not uncommon. Corals, trilobites, and many species of shells, and some encrinites, are found in abundance, especially on Kock river, in the neighborhood of Dixon. The Buff Limestone. Between the Blue limestone and the St. Peters, or upper sandstone, there exists a thin formation known as PRELIMINARY CHAPTER. 17 the Buff limestone, not recognized at all by the early Western geolo- gists. The learned PEECIVAL mentions buff-colored strata or bands, noticed by him in his examinations of the Wisconsin lead regions. WHITNEY, in his geology of the lead regions of Wisconsin, gives it a thickness at Beloit of some forty-five feet, and at Winslow a thick- ness of some thirty feet. Following the section of WHITNEY at Beloit, I have called the similar section at Eockton the buff limestone, and found its thickness to be some forty feet. But most of the sections and outcrops through this part of the State are thinner, averaging perhaps not over eighteen or twenty feet in thickness. This lime- stone is a heavy-bedded dull-colored rock, giving a dull heavy thud or sound when struck by the hammer, as if the sound came from striking a lump of frozen earth. Some of the shaly divisions are very fossiliferous, being covered with shells and fragments of shells. In some quarries near Dixon the strata are massive and solid, and give out almost a metallic ring when struck by .the hammer. In a few instances, as on Pine creek, where the buff and St. Peters sand- stone meet, the line of junction between the two is hard to deter- mine. Hand specimens obtained there seemed to be a mixture of both sandstone and limestone. At other quarries some greenish shales and clays intervened between the two rocks. Some of the layers are a compact, semi-crystalline magnesian limestone, one or two feet in thickness. The upper portions of this formation or division are thin-bedded, and of 'a dull ashy-buff color. They break up into small fragments near the top, and greatly resemble some of the outcrops of the Blue limestone above. The rock forms a good building material, but the superficial area underlaid by it is quite limited in this part of the State. It outcrops around the St. Peters sandstone in narrow bands, and is recognized at Winslow, Eockton, Byron, and a few other places between the two rivers. A few fine fossils, mostly a species of Pleurotomaria, were ob- served ; but, as a general thing, the outcrops examined were almost devoid of fossils. The St. Peters Sandstone. This is the most interesting formation in the series of Illinois strata developed in this part of the State. Its only outcrop is along Eock river, from two to three miles above Oregon to about the same distance below Grand DeTour; and up the streams that fall into Eock river along this part of it, it also outcrops for a few miles ; and a few disconnected fragments have 2 ' 18 ECONOMICAL GEOLOGY OF ILLINOIS. been noticed projecting from a hill-side in Chambers' Grove, a few miles north of Polo. On Kock river the heaviest development, per- haps, in the State may be found. It reaches a thickness here of nearly two hundred feet. Fantastic shaped bluffs of white, brown and fer- ruginous stained sandstone rise along the river banks, and display the coloring, shapes and castellated appearances of the icebergs in an Arctic zone. It is composed of pellucid, limpid, regular rounded grains of pure quartz, and is white almost as snow, when unstained by the oxide of iron percolating through the mass as a watery solution. The slightest cohesion holds these grains together. Indeed, in some in- stances the mass is almost as friable as densely packed sand, and can be penetrated by a blow of the pick, or dug out with a sharp spade. The rock has a saccharoidal or sugary consistence, that would seem to indicate its rapid decay under rains and other atmospheric influences; yet, strange to say, these perpendicular, spire-capped hills resist these influences with great tenacity and success. In some places in Lee county a sort of calcareous cement is inter- mixed, making the rock so hard and semi-crystalline that it is used with success as a building stone. In the softer portions of the rock there are many thin bands of a dark, hard, iron-looking consistence. These weather out in places, giving the appearance of pictured rocks. They are caused by thin crusts of the sandstone having be- come impregnated with a strong solution of the oxide of -iron at various times while the rock was in course of deposition. Many of these broken crusts resemble pieces of old cast-iron pots. Some of them are beautifully marked with what I have been accus- tomed to consider wave or ripple marks. Prof. WHITNEY could find no evidences of the action of water, in his examinations of this rock further south. I have lately come to think, however, that these beautiful markings, instead of being ripple marks, may be wind marks. In examining some sand blows and dunes lately, I found them about their bases in sheltered positions, marked with the same wave-like etchings. However that may be, it is evident that some unusual conditions must have existed when the St. Peters sandstone was deposited. It underlies the whole lead basin, and outcrops heavily for a consid- erable distance around it, reaching on the south into Missouri ; but nothing like it, so far as I know, is found anywhere else on the continent. Its origin is not well understood. The conditions of its deposition are involved in mystery. PBELIMINARY CHAPTER. 19 This is the. lowest rock in the series which outcrops in North- western Illinois. The floor of Eock river, I think, is made up of the top of the Calciferous sandstone, at several places between Oregon and Grand DeTour, but the formation outcrops nowhere at the sur- face, so far as I am informed. The economical geology of this region will be found fully treated of in the detailed county reports, to which this chapter is but an introduction. The ores of lead and zinc, clays, sands, rock for lime and for building purposes, peat, and many ores and minerals of scientific interest, abound, and are fully described in their appro- priate places. JoDAVIESS COUNTY. This large and important county is situated in the extreme north- west corner of the State, It is bounded on the north by the State of Wisconsin, on the east by Stephenson county, in the State of Illinois, on the south by Carroll county, and on the west by the Mississippi river. From north to south it extends twenty-one miles ; from east to west, along the south line twenty miles, and along the north line thirty-six miles. It is divided into twenty-one political townships, not always corresponding in size or shape with govern- ment surveyed townships. These are named respectively," commenc- ing and following the order in which the sections of a regular township are numbered, as follows : Courtland, Apple Eiver, Scales' Mound, Council Hill, Vinegar Hill, Menomone, Dunleith, West Galena, East Galena, Guilford, Thompson, Eush, Nora, Ward's Grove, Stockton, Woodbine, Elizabeth, Bice, Hanover, Derinda, Pleasant Valley, and Berreman. These contain, in all, about five hundred and eighty- nine square miles or sections of land. Pln/sical Features and Configuration. These are more diversified and interesting than are to be met with in any other county in this part of our State. The whole county is a part of the side of an extensive water-shed, with a slope to the southwest. The county is excellently well watered. All the streams flow in nearly the same direction : from the northeast to the south- west. The principal of these streams, commencing at the eastern part of the county and going westward, are : Plum river, Cnmp creek, Eush creek, Apple river, Small-pox creek, Galena or Fever river, Sinsinnewa river, Little Menomone and Big Menomone rivers. JO DAVIESS COUNTY. 21 Apple river and Fever river are considerable streams ; the latter, in high stages of water in the Mississippi river, will float the largest steamers from that river to the city of Galena. Most of the others afford abundant mill-sites for light mills and manufactories. At Hanover, on Apple river, there is quite a heavy power used, for the purpose of driving the machinery in an extensive woolen mill. Along the southwest part of the county ther^e is some alluvial bot- tom land, made up of deep, black Mississippi mud bottoms and sand prairies ; but these are not extensive. Some of the smaller streams have narrow and fertile alluvial bottoms. These are walled in, in most cases, with bluff ranges, more or less precipitous and rocky. The trend of the bluff line along the Mississippi river winds and bends with the general course of that stream. These bluffs are high and gently rounded along the northwestern part of the county, but assume a more picturesque and castellated appearance as they enter Carroll county on the south. It is almost impossible to give a correct description of the surface of JoDaviess county, without a minute reference to almost every township in it. In general terms, there are all varieties of surface found in the northern part of the State. Level prairie, rolling and undulating prairie and oak openings, uneven, hilly, rocky and bluffy timbered and farm-land tracts, may all be found in almost any portion of the county. The eastern and northeastern townships are gener- ally prairie ; soil rich, warm and deep ; some of it regular level Illinois prairie land ; some of it, towards the center and south of the county, undulating, uneven, partly covered with scattering and scrubby tim- ber. The southern tier of townships is uneven, sometimes hilly, sometimes rocky, with some prairie in Berreman, Pleasant Valley and Hanover. The western and northwestern townships are gener- ally timbered, hilly, rocky, and even bluffy. The central townships are generally uneven and partly timbered. The prairies of JoDaviess county are not excelled in fertility by any upland prairie in the State. The soil of the rough, uneven and hilly land, when cleared of its timber and underbrush, and laid open to the genial influences of good cultivation, is quick and fertile, being composed of. a clayey, somewhat marly base. Numerous farms, some of them quite large, opened in the rough lands in every part of the county, attest the truth of this statement, and amply repay their owners for the labor of putting them under cultivation. Some of these reddish clayey soils might not look fertile to the husbandman used to the blacker prairie soils ; but the large yield of cereal grains and grasses would soon convince him that their producing powers 22 ECONOMICAL GEOLOGY OF ILLINOIS. were almost equal to the vegetable moulds and humus-charged soils of the leveler portions of the State. Indian corn, of course, is not so heavy a staple crop here as in other portions of the State farther south; still, good crops are raised with reasonable certainty. Stock-raising is also an important element of wealth in the county. The range is good, and sheltered situations for the winter are abun- dant. The citizens of the county, many ol them, are largely engaged in this very remunerative business. The agricultural resources, stock raising capabilities, and mineral wealth hidden away in the underlying rocks, are all leading elements of wealth in this county. The county has an abundant supply of timber, for its own con- sumption, for many years to come. The oak family is largely rep- resented among its trees; basswood, hickory, walnut, and, in short, all the trees, wild fruits and shrubs catalogued for this part of the State may be found in the bottom timber, barrens and groves. Fruit-growing and vine-raising may both be carried on success- fully. The hills about Galena, and in many other portions of the county, produce the hardy fruits and grapes in great abundance. The business has not been gone into extensively, but there is no reason why wine-making might not be made to pay in favored localities. On the Galena hills I have see'n grape-vines purple with thick hanging clusters, while apple trees near by bent beneath their ripened fruit. The garden fruits attain also to great perfec- tion. A prominent feature in the landscape of portions of the county is a number of natural mounds rising to a considerable height above the general surface. Pilot Knob is the most conspicuous of these. It is about three miles south of the city of Galena, and about two miles from the Mississippi river. It is a conspicuous landmark to tourists and river men passing up and down that stream. Towering above the sur- rounding high bluffs, it reaches an altitude of 429 feet above ordinary water mark in Fever river, according to barometrical measurements made by WHITNEY. There is a chain of some half dozen of these mounds, running northeast of Pilot Knob four or five miles, among them Waddel's and Jackson's mounds, well known local elevations. ' Around the city of Galena there are several mound-like elevations and ridges, the most conspicuous of which terminates in a group of castellated rocks near the residence of Mr. Hallet. These rocks overlook the city, and the crooked valley of Fever river, for some distance. JO DAVIESS COUNTY. 23 Charles' Mound, near the north line of the county, is supposed to be the highest point of land in the State. Its ridge-like, rocky back- bone is 295 feet above the Illinois Central Eailroad track, at Scales' Mound station, 951 feet above low-water mark in the Mississippi river, at Cairo ; and 1,226 feet above low-tide in the Gulf of Mexico. These are the figures given by Whitney. Scales' Mound, about a mile south of the last, is' a well known locality. Around this latter, and within a radius of two or three miles, there are several other similar but smaller mounds. East and southeast are Woods' Mounds, in the south part of Apple Eiver township ; Bean's Mound, near Apple river ; Powers' Mound, in the northwest corner of Eush township ; Paige's Mound, near the south line of Courtland township ; Simmons' Mound, near the north- east corner of the township of Stockton ; Benton's and Bice's Mounds, a little north and west of the latter ; one or two mounds or mound- like elevations east of Elizabeth, whose names I did not ascertain ; an elevated, mound-like plateau of several miles in extent, commenc- ing about two miles north of the village of Elizabeth; and several other such plateaus in various parts of the county. The geological structure of these mounds gives them the appear- ance of gently sloping hills for a part of the distance up their sides, crowned by abrupt, fancifully weathered, castellated rocks, of a red- dish-brown or whitish-yellow appearance. Some of these views, from a distance, have a great resemblance to old mural walls and baronial towers, and vividly recall to memory the wild architectural struc- tures of the middle ages. . Their geology is quite interesting, and will be more fully dwelt upon in a subsequent part of this report. These same Niagara rocks outcrop in long mural escarpments along the Mississippi and Apple river bluffs, and along many of the smaller streams in those portions of the county where this geological formation is heavily developed. The ledges and exposures, and some of the abrupt outliers of the Galena rocks, also present the same picturesque, wild appearance. Some of them present scenes almost as attractive as any in Jackson county, about the Devil's Backbone and the Mississippi Bakeoven. It will thus be seen that the topography and physical features of this county are well marked and attractive in the extreme. 24 ECONOMICAL GEOLOGY OF ILLINOIS. Surface Geology. Alluvium. The small water courses of the county have the usual narrow alluvial bottoms. In some places these spread out wide enough for small farms. Pleasant valley, along the north branch of Plum river, extends from Morseville to the Carroll county line, a distance of some ten miles ; it is from a quarter of a mile to almost a mile in width, and contains some of the very best farming lands in the county. These narrow alluvial bottoms are composed of a rich brown marly soil, made up in great part from the wash and detritus from the hills on either side. In but few places can there be noticed the black silt or mud or washed sand of river alluvium. The valleys are all ancient valleys of erosion, floored or built up by recent detritus from the hills, not transported to great distances nor greatly mixed, and belonging to very recent Quaternary deposits. The Mississippi river bottom, in the upper part of its course along this county, is very narrow in fact, that stream almost washes the rocky base of the bluffs for many miles. There is, however, a chain of sloughs opposite Galena, and along the mouths of Fever river and Small-pox creek, where there is a low alluvial bottom, timber- grown, and made up of Mississippi mud arid sand. This is the flood- plain or flood-bed of the stream, over which the annual overflows of high water extend. Farther down the river this bottom spreads out to several miles in extent. In the western part of the township of Hanover, bottom timber land, alluvial grass land, and a table land high and dry and susceptible of cultivation peopled by a consider- able settlement about Huntsville landing exhibit all the character- istics of the ordinary Mississippi alluvial bottoms. Farther down, in Carroll county, this bottom changes into the broad, well known sand prairie an old, broad, extended, glittering Mississippi sand bar. Loess and Modified Drift. The regular marly Loess of the Mis- sissippi bluffs, such as is found opposite Fulton City, at Warsaw, and at other localities further down, is not a marked feature along the western limits of JoDaviess county. Its bluffs are mostly com- posed of massive rocky formations. The bald bluffs, composed of whitish, partially stratified sands and clays, were not observed ; but there are mound-like elevations, and masses of brown, marly, sandy clays along, among and over-capping some of these chains of bluffs, which undoubtedly owe their origin to the same agencies which deposited the Loess of the bluffs, lower down the stream. JO DAVIESS COUNTY. 25 These brown deposits are Loess marls and clays, slightly modified by local conditions. Within the limits of the city of Galena, and at other points in Fever Kiver valley, and forty or fifty feet above ordinary water level of Fever river, there are heavy outcrops of a well marked, distinctly stratified clayey deposit, which shows every characteristic of the most marked and well defined Loess of the lower Mississippi bluffs. Thin seams of reddish clayey marls alter- nate regularly with thin seams of a whitish, tough, unctious-feeling clay. The seams are from one to four inches thick; the stratifica- tion is complete ; the lithological character seems to be identical ; the thickness is from ten to eighteen feet ; and the extent into the hills indefinite, but probably limited. In the marly seams I found great quantities of a fluviatile shell, in a fair state of preservation. These shells are quite small, running from the size of a wheat grain to that of a large barley corn. I have several times, within a few years, noticed the same shell, or a closely allied species, strewn thick over the silt and mud after the floods of the Missis- sippi had subsided, and the flood bed had become overgrown with a dense growth of grass. Beneath the shadow of the grass the damp ground looked as if it had been thickly sown with large wheat kernels. Subsequent overflows no doubt embedded these, and where antiseptic properties mingled with the silt, they will no doubt be preserved, and present an appearance exactly identical with those picked out of the outcrop near the Illinois Central railroad depot in Galena. It will thus be seen, I think, that the evidences of the disposition of Loess deposits in this county are incontestible. ID the Fever River valley, within the city of Galena, a mile or two above the city, and at several places between the city and its confluence with the Mississippi river, there are well defined river terraces of modified or river Drift. These are about twenty feet above ordinary water mark in that stream. Similar traces were ob- served by Professor WOETHEN at the mouth, and up the valley of the Small-p'ox creek ; and a broad, distinctly marked river terrace may be observed in the lower part of the Mississippi bottom, extending down into Carroll county. Drift Proper, The productive lead field has been written down as "a driftless region;" and to some extent this is true of that part of it within JoDaviess county. But in attempting to account for this supposed absence of the Drift in the lead region, eminent geologists have fallen into a controversy, or difference of opinion. WHITNEY contends that when the lead region was uplifted from the Silurian seas, no subsequent submergence ever took place; and 26 ECONOMICAL GEOLOGY OF ILLINOIS. that all the changes which have since taken place on its surface, have been produced by agencies, such as we now see producing dynamical results upon dry land. When the broadly extended Drift forces whether broad-creeping and grinding glaciers, or broad-water currents, or icebergs and water acting together moved the Drift on its southwest course, according to this theory, the lead region rose as an island in the midst of the moving forces, and the Drift stream was divided thrown to the east and west and united again after passing the obstruction. Such being the case, the lead basin, sup- posed then to have been elevated above the surrounding country, escaped the action of the Drift forces. During all this time, more peaceful geological causes are supposed to have been at work over the uplifted island, whose action has produced all the geological changes supposed to have taken place. Atmospheric and chemical agencies disintegrated the hard Silurian rocks. The surface rocks changed slowly into the clays now overlying the bed rocks, except so far as rains and winds may have transported these clays and subjected them to a mixing process. This being true, the superfi- cial deposits of the driftless lead regions are substantially in situ, at the very places where they were formed by the decay of the parent rock. PEECIVAL believed that the high-water shed, extending from the mouth of the Wisconsin eastward, rose as a reef in the Drift epoch waters, and turned the drift to the west through Iowa, and to the east round the lead region. This reef may have permitted a sheet of shallow water to flow over it, and submerge the lead basin. In this way the action of the Drift forces would be greatly modified. My own observations upon the Drift phenomena in this county have not been altogether satisfactory. In the first place I do not think it a "driftless" region. In addition to the drift pebbles and cop- per nugget referred to, by Professor WOETHEN, as having been found at the California lead diggings, I have observed numbers of large boulders lying over the prairie land in the eastern and southeastern portions of the county; and I am credibly informed that, on the high upland some three miles north of Galena, many boulders of a sort of buhrstone, whose parent outcrop is far north in Wisconsin, are strewn over the ground. Many of the clay deposits covering the very lead veins themselves, do not differ materially from the buff and yellow clays treated and recognized everywhere else in the north- west as true Drift clays. The river terraces and stratified Loess deposits above spoken of; the lithological character of the clays just referred to; the few "nigger heads" and lost rocks found in JODAVIESS COUNTY. 27 several places in the county, show unmistakably, I think, that the Drift forces, especially towards the close of the Drift epoch, had much to do in cutting down, carrying away, and arranging the great rocky formations which once existed, but which have now disap- peared over large portions of the county. Over more than half its area, perhaps, the whole thickness of the Niagara limestone and the Cincinnati shales have disappeared, except the mounds left stand- ing as sentries, at long intervals ; and the very Galena bed rocks below where they used to stand, have had their surfaces denuded, to a considerable extent, in the operation. To one standing upon one of these mounds, and looking over the valley-like expanses be- tween them, with the eye of a geologist, the conviction that he is standing upon the old Silurian level of the country, grows into a certainty. Eroding and denuding influences have removed from three hundred to three hundred and fifty feet of Magnesian lime- stone and shales. It is impossible to suppose that simple atmos- pheric or chemical causes, acting no matter how long, could produce such gigantic results. Many submergencies and upheavals may have taken place ; the dynamical powers of the heavy bodies of water and water currents, and other Drift forces, must have acted long and powerfully in bringing them about. While these things all appear to be true, it cannot be denied that the superficial deposits covering the bed-rocks, are, in part, derived from their disintegration, by rains, frosts and other atmospheric and chemical agencies. I have examined many clay banks through the lead mine region, which bore unmistakable evidences of this. Those peculiar red clays, characteristic of the lead region, if dug into, show, first, the clays and hard-pan, without rocks of any description, but as the deposits are penetrated, rocks begin to appear in de- tached pieces, becoming more abundant at a greater depth, until the regular strata of the bed-rocks are, reached. Now, these pieces are unworn by atmospheric influences ; they lie in horizontal beds, par- allel to the strata below, and are evidently the harder portions of the mass which resisted the influences that changed the rock bed into a clay bed. Nearly all the float mineral or clay bed mineral now found is, also, nothing but the ore which has settled down from the decayed rocks in which it was once held in veins and min- eral-bearing lodes. This is also true of the clays covering some of the Niagara and Cincinnati outcrops or bed-rocks, for they partake largely of the underlying rocks, from which they have probably been derived. I 28 ECONOMICAL GEOLOGY OF ILLINOIS. think a chemical analysis of these clays would show a great simi- larity or exact identity with the rocks under them. Professor WHITNEY'S theory of atmospheric agencies, and no sub- mergence of the lead basin since its upheaval from the Silurian ocean, explains well these unmixed clays, in situ apparently, at the very places where formed ; but it does not explain the great erosion and denudation which has taken place through the productive part of the lead basin, and is utterly inconsistent with the terraces, Loess and Drift phenomena, plainly manifest in almost every part of this county. If we knew exactly what the Drift forces were, and how they acted, we would probably have no difficulty in seeing what influences modified their force in the lead basin. That such a mod- ification did take place in some way, there can be no doubt. The blue plastic clays, which lie near the bottom of the Drift in other parts of the State, are sparingly developed here, so far as I have been able to observe. The boulder drift, and coarse gravel drift, which lie near the top of the true Drift, except the few loose boul- ders already notioed, are, also, substantially wanting in this region. The yellowish brown clays, red Delays, and hard-pan, are devel- oped here to a considerable extent ; but the average depth of the superficial deposits covering the rocks in JoDaviess county, is a good deal less than in portions of the State farther east and south. The great denudation which took place here, seems to have been followed by transporting agencies, which bore away a large portion of the materials thus disengaged, to other regions. The phenomena here observed are probably best explained by sup- posing two epochs, when causes somewhat different in their results were at work. The first was the epoch of Erosion and Denudition, accompanied by vast transporting agencies of some kind, probably flowing water or modified drift forces. During this epoch the Niagara limestone was worn down, and the Cincinnati shales suffered disintegration, and most of the detritus thus formed was removed. The second epoch was one in which the waters or modified drift forces had partially or wholly subsided ; chemical and atmospheric agencies worked upon the comparatively naked rocks ; and the lead basin clays settled down in the places where the underlying rocks had decayed. Such a condition of things would, I think, explain all the phenomena observed in the lead region of this county. How far it might apply to other portions of the northwest lead region, I am unable to state. The Niagara Limestone. All the mounds, mound-like ridges and plateaus mentioned in speaking of the topography of the county, are JO DAVIESS" COUNTY. 29 capped by massive irregularly-bedded dolomitic Niagara limestone, ranging in thickness from about fifty to one hundred and seventy- five feet. The castellated appearance of these outliers of this great formation, as they cap these mounds, has already been mentioned. Tapestried with lichens and mosses, of a dull brown or red color, with castellated and fantastic forms, these rocks at once attract the attention of the most careless observer. In addition to the mounds, they cover other portions of the county in the south and southwest ; and their ledges and exposures all round the edges, along the bluffs, and where the streams have cut deep channels into their midst, show the same massive, ragged and picturesque appearance observ- able on the mounds ; except that they resemble more, long, irregu- larly-shaped reddish-brown mural escarpments or walls, carpeted with soft green mosses and feathery ferns. The superficial area of the county, covered by these rocks, is about as follows, in a general and approximately correct boundary statement : The high bluff range, about Pilot Knob, is capped by this rock. It commences a short distance north of the knob; the knob itself is a high pile of Niagara limestone, resting upon the Cincinnati shales ; and the bluffs from thence to Small-pox creek continue to show it along their summits. From this latter stream to the Car- roll county line, near the point where it crosses Apple river, the upper part of the bluffs are composed of the same rock, and some grand outcrops of almost beetling crags may be seen here. These outcrops extend far back from the brow of the bluffs, and are the bed rock over all that high plateau between the Small-pox creek and Apple river, extending in a strip several miles in width to the north- east, to about the township line, between ranges 2 and 3 east. Still farther to the northeast, and separated from this large field by some narrow belts of Galena rocks, about the head waters of Apple river, is a mound-like plateau or table, about four miles long and two and a half wide, and grouped round it are a number of the mounds heretofore named. As already observed, these are all Niagara limestone structures, built upon the underlying Cincinnati shales. Terrapin Ridge, about two miles south of Elizabeth, is the north- ern projection of another high table land of exactly similar charac- ter, extending south and a little west, between Apple river and Rush creek, nearly or quite to the Carroll county line ; but this table land does not approach close to either of these streams. About two and one-half townships in the southeast corner of the county, are underlaid by this rock. This field extends from the 30 ECONOMICAL GEOLOGY OF ILLINOIS. east and south county lines to the Bush Creek valley, on the west, and nearly to Morseville on the north. Plum Eiver valley and Dutch Hollow, in this field, cut down to the galena, in places, and show the gentle talus-covered slopes and outcrops of the Cincinnati group at many places along their sides. The probahle extent of the county covered by this formation, is a little less than one-third. There are many places throughout this extent where the eroding streams have cut down through the Niag- ara, into the Cincinnati shales, and even reached the Galena lime- stone below both. Such is the superficial area covered by this rock, stated approxi- mately. Its lithological character has been so often written that it seems superfluous to speak of it here. The rock is generally mas- sive, irregularly bedded ; tough ; of a yellowish color on fresh frac- ture, but weathering to a reddish-brown. It is full of chert bands; and some of the Niagara hills are macadamized with a thick floor of finely broken, dendrite-speckled flints, which remain from the decay of the strata formerly enclosing them. These flint hills, or flint covered hills, are characteristic of the Niagara limestone form- ation. The maximum thickness of the Niagara limestone in this county cannot be accurately stated. The denudation which has taken place on ifs top, and the difficulty of ascertaining the bottom, make it almost impossible to measure its thickness correctly. Its heaviest outcrop is probably along Small-pox creek, where it reaches a thickness of over two hundred feet. As developed in this county, it is exceedingly homogeneous in character the varieties observed at Kacine, LeClaire and Cordova, being wanting. In chemical analy- sis, lithological character, and general appearance, it is very similar to the Galena limestone. If a difference can be detected, it is less sandy and crystalline, and tougher than the latter formation. Its type or characteristic fossils are also different. These are chiefly Pentamerus oblong us; Favosites favosa; JIalysites catenularia; Astroerium venustum; and one or two species of Stromato- pora formed corals. The Pentameri are the traditional "petrified hickory nuts," so often spoken of by the miners and well diggers. Huge blocks of the stone, in places, are sticking full of them. On the silex-sown hills, bushels of rough weather-stained specimens of the Favosites can be collected. These old Niagara seas swarmed with the coral builders ; and many of the Niagara beds of rock were little else than coral reefs. The Cincinnati Group. The green and blue shales and limestones of the Cincinnati group underlie the Niagara limestone wherever the JO DAVIESS COUNTY. 31 latter is developed in the county. There are not many natural out- crops of these shales, and they never stand out in ledges or rocky exposures, unless where quarries are opened into the covered rocks. Even where quarries are opened into this formation, and then abandoned for a few years, the rapid disintegration soon covers up the rocks with a gently sloping talus. The parts of the county underlaid by this formation can be told at a glance. All around the mounds and mound-like elevations, all around the outer boundary lines of the Niagara formation, up either side of all the valleys of erosion which have cut through it, the gentle slopes extending from the general level of the country up to the base of the bold Niagara exposures, are underlaid by rocks and shales of the Cincinnati group. These slopes may be represented by a narrow band two or three hundred yards more or less in width, encompassing all the Niagara fields and outliers, in the county, and running up either side of all the valleys that are cut through it. When this is said, the superficial area underlaid by the Cincinnati group is as well indicated as it could be by many pages of description. One or two localities, however, deserve a pass- ing notice. At the northern terminus of Terrapin Eidge, near Elizabeth, the milky looking clays and shales are washed and furrowed out by the rains, exposing many fine specimens of the hemispherical-shaped coral Ch&tetes petropolitanus. I have found dozens of good specimens of this coral in the clay-washed road at this locality. East of Scales' Mound the track of the Illinois Central railroad is laid for several miles almost upon the top the Galena limestone. Several rather heavy cuts in that locality show good exposures of the overlying Cincinnati shales. These beds contain in certain layers a very great abundance of minute fossils, principally a small Nucula. The general character of this group in JoDaviess and Carroll counties is almost identical. The upper layers are thin-bedded argil- laceous and siliceous shales, of a light-buff or creamy color. Where thick-bedded enough to quarry, the stones have a kiln-dried, dusty appearance. Lower down, the shales become blue or greenish in color, sometimes separated by thin bands of green, marly clay ; still lower, some massive strata of a deep ultra-marine blue color may be found, exceedingly hard, and giving out a clear, ringing sound when struck with a steel hammer; below these there is found in some localities a black carbonaceous shale, so highly charged with carbon as to burn with a bright flame as though impregnated with oil, and the bottom of the deposit is made up of thinner strata of 32 ECONOMICAL GEOLOGY OP ILLINOIS. alternating yellow, blue and green shales and clays. Wherever the rain cuts through the soil into these shales, or the little streams wash them, the wet clays have a greasy look, and the trickling waters a creamy and greenish color. There are no gradual beds of passage into the overlying Niagara or the underlying Galena lime- stones, but the formation preserves well its distinctive characteristics. The beginnings of its foundation stones and its cap-rocks are always easily recognized. The thickness of the deposit cannot be accurately stated. A true section, as developed in the Mississippi river bluffs, from Bluffville, in Carroll county, to the mouth of Fever river, would run from eighty to one hundred and twenty feet. In the interior of this county it nowhere, perhaps, reaches to one hundred feet, and in some places it is only from forty to sixty feet. The deposit is full of well-preserved fossils. The Orthoceratite beds in Dubuque county, Iowa, have long been famous for the number of well-preserved Orthoceratites with which they are crowded. The Chfgtetes petropolitanus is a characteristic fossil, and is found in great abundance at Elizabeth, and in the washes and 1 ravines at other places. Fragments of a branching coral, and the small, bud- like heads of an encrinite, are generally found in the same localities. In a few places I observed immense numbers of the fragments of Isotelus gigas ; also several species of Orthis, among them Orthis lynx; associated with Ambonychia radiata, Strophomena alternata, frag- ments of two or three species of Orthocera, and one or two of the new fossils described in the third volume of the Illinois Geological Reports ; Strophomena imicostata and Tentaculites Sterlingensis were also observed. The Galena Limestone. This is the great bed-rock of the county. From Dunlieth to about the mouth of Small-pox creek it forms the rocky bluffs on the Mississippi river. All the northwestern, northern and northeastern part of the county, except a few of the mounds heretofore named, is underlaid by it. The eastern part of the county, extending a short distance south of Morseville, is also underlaid by the same rock. All the larger streams in the county, including Sinsin- newa, Fever and Apple rivers, Rush, Small-pox and Plum creeks, with their principal tributaries, flow along the surface or cut into this formation. It immediately underlies the surface deposits of something like two-thirds of the county. The maximum thickness of the Galena rocks in this county is not known. It is probably not far from three hundred and fifty feet. At Elizabeth shafts are sunk one hundred and fifty feet deep, and what JO DAVIESS COUNTY. 33 is known as the flint strata, among miners, was not reached. At the places of these shafts the Galena had been considerably denuded. The flinty strata generally is characteristic of the middle of the formation. It may be, however, that the estimate from this basis is too great. No outcrop observed was over about two hundred feet thick. Its lithological and stratigraphical character is too well known, and has been too often given in these reports, to require an extended notice here, as all into whose hands this report will be likely to fall will probably have access to those descriptions. The rock is a thick- bedded, sub-crystalline, compact, cream or chrome-colored dolomitic or magnesian limestone. It weathers out into forms almost as fan- tastic and picturesque as the Niagara above it. Along the streams its weathered-out ledges present the same castellated and mural appearances, and some of its outliers rise into towers and chimneyed shapes of the most striking outlines. At Dubuque, or rather oppo- site Dubuque, at Dunleith, a curving tunnel has been cut through the solid rocky bluff, some eight hundred feet in length, for the purpose of permitting railroad trains to pass over the new 'bridge across the Mississippi river at this locality. This tunnel is about twenty-five feet above the Trenton or Blue limestone. The base of the Galena, here, is not far from the water-level of the river. The rock removed from the tunnel is not so yellow in color or granular in structure as that obtained from the upper parts of the deposit. It shows the beginning of the beds of passage into the underlying Blue limestone of the Trenton.- The rock removed from the shafts and mines at Morseville and Elizabeth has a granular appearance, and a color peculiar and difficult to describe a color between a cream-yellow and a cerulean-blue, if such a color can be imagined. There is also, mingled with this, a greenish rock, corresponding with the rock found at the green rock openings about Mineral Point. Other peculiarities of this limestone will be noticed when I come to speak of the lead deposits, under the head of "Economical Geol- ogy." Fossils are not so numerous in the Galena limestone of this county as in that of Carroll, Stephenson or Winnebago. At Morseville, among the stones and debris thrown out from the lead diggings, I obtained several fine specimens of Bellerophon, the only fossil there observed. Illanus crassicanda and I. taurus have both been found at Galena; a large species of Cypricardites is also frequently found, especially in the quarries in Carroll county. Murchisonia bellicincta and 3 34 ECONOMICAL GEOLOGY OF ILLINOIS. Receptaculites Oweni, two of the most characteristic Galena fossils, are found less frequently here than in any other portion of the formation in neighboring counties. A section of the largest Orthoceras ever discovered in the lead region, perhaps, was found in the Galena limestone at Morseville, some two years ago, by some of the miners. It was eighteen or twenty inches long; a siphuncle nearly three inches in diameter, projected about four inches at one end ; the septa, somewhat loose, looked somewhat like a ribbed human body with a projecting neck. Of course, those who saw it supposed that a petrified human trunk and neck had been discovered. Trenton Limestone. This limestone is only met with in two local- ities in the county. At Dunleith, and a little above it, there is a, low outcrop along the banks of the Mississippi river. It is here a light bluish-gray rock, regularly and rather thinly-bedded, with shaly partings, showing many of its characteristic fossils. These layers are near the top of the formation, and have some of the character- istics of the superincumbent Galena. They, in fact, begin to partake of the nature of the beds of passage into that rock. At Dubuque splendid specimens of Graptolites have been found in the Trenton; also very finely preserved eyes of Trilobites. Other exposures of this limestone may be seen along the north branch of Fever river, commencing about three miles northeast of Galena, and continuing until the Wisconsin line is reached. The outcrop attains a thickness of about twenty-six feet at its heaviest exposure, at Tuttle's mill. It is made up of thin-bedded limestone, a rather thick-bedded strata of glass rock, and grayish heavier- bedded limestones. Near the forks of Fever river a cut of the Illinois Central railroad shows a similar but thinner section. Many of the well known fossils of this formation are said to have been found at these outcrops. But the conditions were not favorable for obtaining fossils at the time I was there. Thife is the. lowest formation anywhere outcropping in the county, or that can be regarded as belonging to a section of JoDaviess county rocks. We are now prepared to give that section, naming the approximate average thickness of the formation : Section of JoDaviess County flocks. Feet. Quaternary Deposits. Alluvium, Loess, river terraces, clays, sands and hard-pan, 20 to 75 Niagara Limestone. Heavy-bedded, reddish-brown, dolomitic limestone, weathering into cliffs and castellated exposures, similar in lithological charac- ter and appearance to the Galena limestone 40 to 200 Cincinnati Group. Green and blue and buff-colored shales; thin-bedded gray limestone, and hard, thick-bedded, glassy rocks 42 to 80 JO DAVIESS COUNTY. 35 Feet. Galena Limestone. Heavy-bedded, cream-yellow, dolomitic limestone, the lead rock of the Northwest; somewhat granular and crystalline, and showing beds of passage into Trenton below 100 to 275 Blue Limestone. Thin-bedded gray limestone and shales and glass-rock of miners - 10 to 26 Economical Geology. Building Stone. There is the greatest abundance of good building stone in this county, so distributed as to make it of easy access to all its citizens. All the formations are quarried. In Pleasant Valley a number of good quarries are opened in the Cincinnati group of rocks. These quarries are in the brows of the hills, on either side. The stone obtained is sufficiently thick-bedded and compact to make a good building stone. It has a dry, dusty, kiln- dried appearance. Several farm houses are built of this material in the valley. So far it seems to answer well for farm uses, without exhibiting a tendency to disintegrate. The best of it would, I think, be unsafe for massive and long enduring masonry, but for light masonry it seems to answer well; and its convenience of access, and the ease with which it can be quarried, will always cause its out- crops to be kept open and worked. The abundance of better build- ing material in most parts of the county doubtless prevents its extensive use in other places where it could be easily obtained. The Blue limestone outcrops, along the north branch of Fever river, afford some good building stone. This is a light-gray lime- stone, rather thin-bedded, and of enduring properties. The outcrop at Dunleith also splits into a conveniently handled stone, and is used extensively for economical purposes. The massive ledges, exposures and natural outcrops of the Niagara and Galena limestone along nearly all the streams, in the brows of all the bluffs and hills, and in all those parts of the county where these heavy deposits are the bed-rocks, furnish an unexhaustible supply of a coarse, enduring, valuable stone, suitable for all sorts of heavy masonry, such as bridge piers and abutments, foundations, cellar walls, and even public buildings and private residences. They require considerable dressing for these latter purposes, but when dressed into good shape their rich, warm, brown and cream colors, and the fact that they season into almost the hardness of a granite, and have an enduring, solid, substantial appearance, makes them prominent among the materials of economical value in the county. Lime. We know not to what extent lime is burned in the county. The abundance of timber and the abundance of good magnesian 36 ECONOMICAL GEOLOGY OF ILLINOIS. limestone afford all the facilities for manufacturing large quantities of a good, coarse, strong lime. Clays and Sand. The clays associated with the Cincinnati shales are sufficiently pure to furnish a potters' clay good for the manu- facture of common crockery ware. At Elizabeth I noticed several outcrops of this potters' clay in some of the streets and lots of the village. Four or five miles south of Elizabeth, on the Mount Carroll and Galena road, the Jenkins pottery is located. This establishment has been in operation for quite a number of years, and has built up quite a remunerative business. The clay is obtained near by. It is not altogether pure and free from foreign substances, but these difficulties seem to be mostly overcome by the processes through which it is put in manu- facturing. The result is a ware largely used in this part of the State, as the Jenkins pottery wagons are well known in all the neighboring towns, villages and cities. Common yellow and red clays, for ordinary brick, exist every- where in the greatest abundance. Sand, suitable for building pur- poses, is not so universally distributed, neither is it so scarce as to be a matter of serious inconvenience. The Associate Minerals. Associated with- the galena, and deserv- ing a passing notice before that important mineral deposit is referred to, are several other mineral substances well known in the lead region. The most important of these is the sulphuret of zinc, blende or "black jack" of the miners. This is a useful ore of zinc, but is quite difficult to reduce. In the lead region it is not considered of economical value. The carbonate of zinc, smithsonite or "dry bone" of the miners, is considered a more valuable mineral. A furnace for its reduction has been in operation for some years at LaSalle, and has proved a financial success. Iron pyrites also occur in connection with these minerals in considerable abundance. At the celebrated Marsden lead all these associate minerals may be seen associated with each other and with the galena, with the Galena limestone, and with spar and other substances. This mine has afforded the best cabinet specimens of these minerals in com- bination to be found anywhere in the lead regions. Brown hema- tite, and several other mineral substances, occur in occasional small quantities, but they are not of interest in an economical point of view. None of these associate minerals have become articles of commerce, except, perhaps, the carbonate of zinc ; and it is doubtful jf even that exists in sufficient quantities to make it an article of value in the economical resources of this county. JO DAVIESS COUNTY. 37 Galena or Lead Ore. The great mineral interest of the county, as every one knows, is lead. Indeed, it is second to no mineral interest in the State, except that of coal. The leading ore of this metal has given its name to the great and important rocky formation in which it is chiefly found in this part of the country, to an important city in the midst of its heaviest deposits, and to the township in which that city is located. The scope of this county report does not embrace a very extended essay upon the mining or metallurgy of lead, or a topographical survey or description of the crevices, leads, lodes and diggings, nor a scientific discussion of the modes of occurrence and phenomena observed in its workings. It is rather the province of this report to present the geological formations of the county, and some general remarks upon the extent of its mineral and other resources. The "Lead Eegion" has been closely examined and ably written upon by Prof. J. D. WHITNEY, for the three States of Illinois, Wisconsin, and Iowa. It will be unnecessary to repeat here what he has pre- sented so well in the first volume of the Eeports of the Illinois Geo- logical Survey. That volume will be' as accessible to the common reader as this, and to that volume we refer the reader for surveys, and descriptions of the crevices- and leads, and a detailed account of the different diggings, their positions, peculiarities of form, extent of working, amount of ore produced, and facts collected in regard to them. It would be useless to write these things over again ; and if it was not, my knowledge of the lead region and opportunities of investigating its facts and phenomena have been far too limited to undertake the task. A brief resume of some of the facts and history of lead and the lead region may not, however, be out of place. Galena, or the sulphuret of lead, called in the common speech of the lead region "mineral," when pure, is composed of 86.55 pure lead and 13.45 sulphur. It crystallizes in the form of the cube and its secondaries, has a perfect and easily obtained cleavage, and a bright, silvery, metallic luster on fresh fracture. The lead ore ob- tained in this county is nearly pure galena. It sometimes contains faint traces of silver. The discovery of this lead was made in an early period. There can be no doubt, I think, that the early voyaguer, trader v and explorer, LE SUEUR, on the 25th day of August, A. D. 1700, discovered and described Fever river under the name of "The Eiver of the Mines." From this, and the description of a mine found, in his journal, he is generally considered the discoverer of the Galena lead mines. Subsequently to this, and prior to the workings of these mines by 38 ECONOMICAL GEOLOGY OF ILLINOIS. white men, they were undoubtedly worked to some extent by the Indians, in their rude way. These primitive miners or rather their squaws, perhaps rudely drifted into the hills, and loosened the mineral by building fires against the rocks and then throwing water on them, as ancient mining was once carried on in the copper mines of the Lake Superior region. Some eighty years after this the wife of an Indian chief, Peosta by name, struck a lead just below the city of Dubuque, which was worked by Julien Dubuque, under per- mission from the Indian tribes. In 1819 the-present city of Galena was first settled, by a man named Bouthillier. In 1820 several others joined him, and a trading house was opened by Jesse W. Shull and Dr. Muir. The adjoining country was a wilderness. By this time the Galena mines had begun to attract attention. In 1823 emigration was pouring in lively. The government had reserved all its mineral lands in this part of the country. In this same year Lieutenant Thomas was sent here by the United States to look after these mineral lands. He granted leases, collected rents, and looked after the mines generally. In 1827 population had so increased that a village was laid off on the present site of Galena, and named from the mineral found on its site and around it. There is a dispute as to whether Lieutenant Thomas or Dr. Muir named the village. The authorities differ on this proposition. In this year permits were given by the government to occupy and improve lots. The possessors of the permits were liable to surrender them to the gov- ernment tipon thirty days' notice. These permits were poor titles ; but the people had no better up to 1836, at which time Congress confirmed the titles of those in actual possession of the town of Galena, laid off into lots by act of Congress, in 1829. Previous to 1827 the leasing policy of the government had substantially failed, and the miners were working wherever they could obtain mineral, without regard to the claims or ownership of the government. The mineral lands, shortly after the first settlement of Galena, had been turned over to the War Department, and the leasing or permit system was continued up to 1846, every year running the government into debt. In this year a law was passed by Congress, throwing the mineral lands into market, and in 1847 the mineral lands in JoDaviess county were brought into market and sold to actual purchasers. During all this time other settlements had sprung up. the most important of which was the trading post called "The Portage," just below the present site of the city of Galena. The Indians swarmed over the lead region at the time of its first settlement. Their squaws discovered many mines, worked them to JO DAVIESS COUNTY. 39 some extent, and traded the mineral to the white settlers. Among these early mines was the "Buck Lead," near the present site of Galena, discovered about the time of. its first settlement. From 1827 the mines rapidly grew in importance and multiplied in number. From 1840 to 1850 the greatest degree of prosperity was reached in the mines, about midway between those years being the very acme of mining prosperity. Galena became the mining metropolis of the Northwest. Thousands of rough miners swarmed through her streets. All sorts of moving vehicles were seen in her thoroughfares, and every language was spoken, every costume worn. The miner generally spent all he made, was poor, and held his own remarkably well. And that reckless spirit, bred of all uncertain pursuits, was abundantly manifested among the miners who assem- bled in the lead region. Card-playing and whisky-drinking, quarrel- ing, and that rough, desperate life developed among adventurers of all classes gathered about Galena, was characteristic of those as of all other mines. But in the midst of it all, the city of Galena grew to unexampled prosperity and wealth, and for hundreds of miles round was the center of commerce and trade for the whole country. Treasures came up out of the ground, flowed into the city, and there remained and built it up. The discovery of the California gold mines swept from the lead mines all that floating part of its population, ready for a new excitement, and also much that was of a more permanent nature. The lead mining interest rapidly de- creased in importance, until the financial troubles of 1857 drove many back to mining as a matter of necessity. At the present time considerable attention is paid to mining, and it is probably a fact that mining labor is better and more uniformly paid now than at any other period in the history of the mines. With all the vast amounts of mineral found, it is also a fact that but a very small proportion of the ground has been proved. We cannot arrive at even an approximately accurate amount of the mineral mined in JoDaviess county. According to Mr. WHITNEY, the amount of lead received at Chicago and St. Louis, as per records of the Chamber of Commerce and Board of Trade, from 1853 to 1859, including both years, was about 181,000,000 pounds. This was from all sources. Of this amount he thinks about one-sixth was derived from mines in Illinois, almost exclusively in this county. This would give about 30,000,000 for this county for that period, which period was the least prosperous time for mining known to exist for many years. From the detailed descriptions given of particular leads and ranges, by the same gentleman, in the first volume of the geological 40 ECONOMICAL GEOLOGY OF ILLINOIS. report of Illinois, we find that he gives the produce of certain enumerated mines up to that time at about 64,000,000 pounds. The Apple River diggings are supposed to have produced from one-half to one million of pounds. The Elizabeth group of mines are stated, by Henry Green, Esq., an old miner nnd smelter, to have produced from 60,000,000 to 75,000,000 pounds. Mr. Green is probably below the amount actually produced. The Vinegar Hill diggings, being a group of about forty lodes or mines, are supposed to have produced 100,000,000 pounds. This statement is made upon the authority of Mr. HOUGHTON'S pamphlet upon the Marsden lead. From the same authority we learn that the maximum production of the JoDaviess county mines, in 184G, was 56,000,000 pounds. The Council Hill mines are supposed, by D. Wilmot Scott, Esq., to have produced 19,00 J,000 pounds. 'The Morseville mines are stated to have pro- duced from one-quarter to one-half million pounds. Captain BEEBE stated a few years ago that five furnaces were in operation in the county, smelting annually 8,750,000 pounds of pure lead, some of which was obtained outside of the county. The Marsden lead is said to have produced 3,000,000 pounds of mineral. A writer in Harper, for May, 1866, states that the amount of lead shipped from the Galena mines from 1821 to 1858 was 820,622,839 pounds, and the value of lead shipped from 1821 to 1865 was not less than $40,000,000. The New California diggings, a few miles south of the Marsden lead, has been yielding a great deal of mineral since their discovery, but I have no means of knowing the amount. These are but a few of the figures and statistics. Hundreds of small ranges, mines and leads have not been mentioned. Multitudes of surface diggings have been carried on, for the purpose obtaining "float mineral,'.' none of which were very extensive, but the sum total of which aggregated, a great deal of lead. From these figures and they are imperfect enough it can be seen that the mineral interest of this county in the past has been a matter of great magnitude. Together with Shullsburgh, Mineral Point and Dubuque, this Northwestern lead basin has been, and yet is, one of the greatest mining localities in the world. The superficial area of the county underlaid by productive lead deposits, so far as known at the present time, is limited, embracing but a small fraction of the area of the Galena limestone. The lodes or ranges are principally located in groups. The diggings, mines or workings are in patches, but seem to have many features in common. The most southern productive mines in the county are on the great east and west range of mineral passing through and just north of JO DAVIESS COUNTY. 41 Elizabeth. This mineral range commences at the mouth of Yellow creek, a few miles southeast of Freeport, in Stephenson county, where an old shaft exists, which used to be heavily worked a good many years ago. The next group of mines on this range to the west is at Morseville, in the southeastern part of JoDaviess county. Here lead has been mined more or less for many years. Several, men have accumulated a competence, especially the former proprie- tors of the old Price lead. The workings are shallow, and the water strong at twenty-five or thirty feet deep. Prospect holes cover the hill sides, and piles of red clay indicate them along many of the ravines. The following ranges or leads are worked at the present time : the Blair range, about one-fourth of a mile west of the village, near the road ; the Company lead, a little south of the village ; Clevinger & Mitchell's range, just south of Mr. Morse's house ; Mumma & Livingston's lead, west of the village, which is the old Price mine; and a lead called the Lyons lead. No one seems to know the amount of mineral produced from these mines. One gen- tleman informed me that it had been about one-half million of pounds. At the present time one or two of the leads are furnishing a considerable quantity of excellent looking heavy lead ; some of it is in large cubes. The stone thrown out from these leads has a granular, greenish-blue look, resembling what is called the green openings of the Wisconsin lead-bearing rocks, but probably higher up in the series. The next heavy mines westward, on this same mineral range, are the groups at Elizabeth and Weston. About 2,500 acres here are prospected over and mined in. It is an irregularly shaped tract of land, about six miles long from east to west. The village of Elizabeth is located upon its southern edge, a little east of its center. The most extensive lead now worked is the Wishou diggings, dis- covered some two years ago in a cultivated field, about a mile north of the village. During the last year this mine has turned out nearly forty thousand dollars' worth of mineral. The mine is now worked by a company, under the superintendence of Dr. Little, of Elizabeth. A strong steam engine runs night and day, and gangs of men relieve each other every eight hours. The workings have reached thirty- five feet below the water level. The shaft is about one hundred and fifty feet deep, and still going deeper. The mineral is found princi- pally in vertical openings, in some places several feet wide, and full of clay, loose stones and chunk mineral. The company are driving their drifts in several directions, and at several different levels. The object now seems to be to develop the mine, and not simply to obtain 42 ECONOMICAL GEOLOGY OF ILLINOIS. mineral. Many heavy deposits are passed and left for future work- ing. The prospect of a rich future yield in this mine is very encour- aging. I spent about two hours in the bowels of the earth here, and then explored but a few of the horizontal drifts. The old Haggerty diggings, the Van Meter range, Stone's field and Kilpatrick's field have all furnished abundance of mineral, and some of them have been worked for 35 years. The oblong tract of ground above men- tioned has been prospected over and mined in extensively. Deep crooked holes, red clay and stone piles, and timbered shafts might be counted by the score. It would be impossible to give the names of ah 1 these. The Elizabeth mines were discovered at a very early day, and worked to some extent. In 1:46 more than 800 miners are said to have been engaged in mining about Elizabeth and Weston. At this time one-ninth of all the mineral raised in the lead region is sup- posed to have been obtained here. Elizabeth and Weston were both swarming, active towns. Lead mining, in its glory, was actively engaging all classes of citizens, and the highest financial prosperity was enjoyed by all who depended upon the trade of mining and the products of the mines. The working out of some of the heaviest superficial deposits, and the discovery of the California gold mines, caused mining to rapidly decline. These mines soon, therefore, fell into disuse and neglect; but they are again assuming something of their former importance. At the present time labor in these mines is better paid than at any other period since their discovery. We mean by this that the general mining labor of all the mines, taken together, will pay a greater average remuneration than in former days, when the few made fortunes and the many only ordinary mining wages. There is from twenty to thirty-five feet of the "flint-rock" above the water level. The flint, on the higher levels, is from 130 to 150 feet below the surface. The crevices gradually close before reaching the flint rock. The easily worked perpendicular crevices above the flint strata were first worked out, and then the mine was generally abandoned. Another observation worthy of notice is, the local ele- vations and dips in this group of lead mines. The flint strata out- crop at the side of the Galena road, in a ravine about two miles northwest of Elizabeth. This outcrop is a few feet above the water level of the brook near by. At Wishou's shaft, a short distance east of the outcrop, and near the top of the hill, the miners are working thirty-five feet below the water level of the mines, and still the flint is not reached. The water level in the mines rises slowly as the JO DAVIESS COUNTY. 43 hill is penetrated ; but this rising of the level could make but a few inches or feet difference at most, while the fact seems to be that there is more than forty feet difference between the bottom of the shaft and the flint outcrop on the road, and no flint is yet reached in the shaft. In other localities the same thing has been noticed. In prospecting for deep mining in this region, this fact may aid in coming to a correct conclusion as to the probable location of lead deposits. Leaving the Elizabeth lead fields, the next heavy mines are found a few miles west, on the east and west slopes of the bluff range, bordering the Mississippi river. These are the New California mines, discovered accidentally, only a few years ago, by a fisherman, who resided in a wild glen on the Mississippi river. At this point the rocky bluffs rise abruptly. The ranges are found by drifting into them a little above the water level, going in where a crevice is noticed rising vertically through the rocks. The mineral found is heavy mineral, existing in large cubes or cogs in some instances. It resembles the large bodies of mineral found in the Marsden lead. On the east slope of the bluff range, where the hills fall away grad- ually to the level of the interior, several lodes are struck by sinking shafts down to the ranges. The following ranges have been struck in these mines, and perhaps a few others, the names of which I did not learn : Wise range, McKenda & Graham, Davis & Brownell, Bernard & Co., Lester, Sanders & Hony, Felt & Clymo, Wakefield & Co., Marble & Young, Dye & Co., Samuel Taylor. Other valua- ble ranges will doubtless be discovered when all the crevices are examined. West of the Mississippi river, in the Iowa bluffs, the same great mineral east and west range has been found. We have thus fol- lowed it almost entirely across the lead basin, and shall now leave it in the Iowa bluffs : Five or six miles north of the New California diggings, the cele- brated Marsden lead may be found. The discovery and history of this great mine was truly wonderful. Some light float mineral had been found in shallow diggings. Thirteen or fourteen years ago the proprietor of the rough farm, which had been purchased by him for stock and dairy purposes, had occasion to drive a stake into a spring, and in so doing heavy mineral was struck. Mr. Stephen Marsden was then the owner of the farm. By following up the discovery, he soon found himself the possessor of a fortune. A succession of openings in the rock, each deeper than the other, were found to be filled with strong mineral. These openings have been followed to the 44 ECONOMICAL GEOLOGY OF ILLINOIS. depth of about 95 feet, and I am informed that nearly 7,000,000 pounds of excellent mineral have already been taken out. Only about one acre of ground has been worked over in obtaining all this mineral, and the prospects of other heavy bodies of lead being found, both below the present level worked, and on ether parts of this farm, are said to be very promising. This farm and mine has recently been sold by Mr. Marsden to an eastern gentleman, and a company organized to work this mine on the most approved and extensive plan. This range is celebrated not only for the amount, but for the variety and beauty of its mineral deposits. Large cubes and dia- mond-shaped masses of lead ore have been found here, perfectly coated with a beautiful covering of iron pyrites. Galena, black-jack, spar, and iron pyrites are found in wonderful combination, furnish- ing the finest cabinet specimens found any where in the lead region. The Marsden lead, the New California diggings, the Ambruster & Co. lode, recently discovered, and most of the mineral found along the western limits of the lead field in this county, have certain re- semblances, both in the character of the lead ore and its associated minerals, not observed in the mines in the eastern part of the county. The next important group of ranges to be noticed, is within and immediately around the city of Galena. The following are the names by which some of these ranges are known. * There are many others whose local designations are not now accessible. Some of these are not now worked. They are mostly comparatively shallow diggings : Buck, Doe, Harris Leads, Kringle, Gaffner, Hog Range, Tomlin & Burrichter; Frysinger, Crombacker, Tomlin, Evans & Adams, A. C. Davis, Ambruster & Co., Ottawa Diggings, Drum, Rare & Co., Bennenger & Co., Graves, Comstock. & Rosemeyer, Wallon & Quick, Sanders & Co., Muldore, Bolton, Stephen Marsden, Allenrath, Eagan, J. E. Comstock, P. Smith & Co., Hostetter & Co., Duer & Co., Allendorf & Co., Tom Evans, Britton & Wilkins, Cady Range, Roberts Range, Wm. Richards, Wilcox & Co. In addition to the above named ranges, Mr. WHITNEY, in the first volume of the Geological Survey of Illinois, gives the names of some others not included in that list. These are the Kloepfer Range, Barrow Lot, the Morrelli & Monti group of east and west, the Binsemer Diggings, the groups of small diggings on Furnace creek, the Beber Diggings, the Gaffner and Shuster ranges, in the same group with the Gaffner ; the Whitham range ; the Brendel, Eberhart, Widmer' & Nolt, Monti, and Leonhardt, is another well JO DAVIESS COUNTY. . 45 known group of mines ; the Wallis, Leonhardt and Klein crevices on the Morehead Lot, the Wallis Diggings, and the Mannett & Bas- sett Diggings, the Tourlin Lot, the DeToya Lot, and the Flege Dig- gings, the Lowe Diggings, and the Marfield Diggings. These ranges and diggings are situated within a circle of about three miles in diameter, of which the city of Galena would be the center. They are principally on the west half of section 21, the northwest quarter of section 16, the west half of section 9, the northwest quarter of section 28, east fractional section 8 all in township 28, range 1 east, 4th P. M. ; and on the east half of sec- tion 12, the east half of section 26, the south half of section 14, the north half of section 26, and the east part of section 27 all in township 28, range 1 west, 4th P. M. The Vinegar Hill Diggings are about five miles north and a little east of Galena. The following ranges are known by the following designations : Baily, Gear, Meighen, H. Mann, Indian Feehan, Blood, Campbell & Eeppy, Furlong & Fechen, Talbot, Kennedy, Rogers, Hogan, Gray, Leekley, Beedle, Briggs, Manley, Myers, Bruno, Cottle, O'Mara, K. Orwick, Whim Eange, Hawkin Hart, Trover, Dugan, Liddme, Hoskin, Sidemer, Shattluck, Smelt, 15 Strike, Foley, H. H. Gear, Cooney & Eyan, Cox, Wylram, and Richards. These are located principally on fractional sections 14, 15 and 16, on fractional sections 20 and 29, on sections 21, 22 and 23 all in township 29, range 1 east, 4th P. M. ; and on the east part of sections 24 and 25, township 29, range 1 west, 4th P. M. On the west part of the last section named, on the northeast corner of section 35, and on the north half of section 23, in the township and range last aforesaid, there are also groups of diggings not enumerated in the foregoing ranges. The Vinegar Hill mines are among the heaviest in the lead region, if we consider the amount of mineral they have furnished, but they are not now worked to a great extent. These diggings extend in a somewhat northeast and southwest direction, over a tract of ground about three miles long, and not to exceed a mile in width. The shafts are sunk from about 50 to 90 feet deep, and penetrate in many instances the flint beds of the Galena limestone. About three miles east and a little south of Vinegar Hill Dig- gings, the Council Hill ranges are located. The heaviest ones are situated on the north half of section 25, and the south half of sec- tion 24, township 29, range 1 east. They are known as the North Diggings, and cover a tract of about forty- seven acres, on which is over one hundred veins running northeast and southwest. The prin- 46 ECONOMICAL GEOLOGY OF ILLINOIS. cipal, medium, and smaller shafts, number nearly one thousand. The South Diggings, on the south of the Hill, are of small import- ance. The east half of section 36, township 29, range 1 east, and the west half of section 31, and the south half of section 30, town- ship 29, range 2 east, have upon them diggings, the most important of which is the Eocky Point and Bolt's Lots. Two or three lots and diggings along Fever river, between Council Hill and Galena, have yielded considerable mineral. The Burton, the Beeler, the Allan Eea, the Witmer, and the Wright lots, are the most important of these. The Apple River Diggings, near the station of that name, on the Illinois Central railroad, have yielded heavy bodies of ore. It is generally found in east and west shallow crevices, which did not hold their richness to any considerable depth. A few scattered and unimportant diggings around Warren, com- plete the list of diggings or sub-districts into which the lead fields of this county may be divided. It will now readily be seen how small an area of the Galena rocks are productive lead-bearing rocks. All grouped together, would make perhaps less than a township of land. Price. The following table shows the price of mineral per thous- and pounds, for the last sixteen years, as delivered by the miner to the purchaser, at the mouth of the shaft. The ore was always paid for in gold, until the greenback era drove gold out of circulation: 1853 $37 1861 $28 1854 38 1862 40 1855 32 1863 55 1856 35 1864 75 1857 34 1865 65 1858 29 1866 60 1859 30 1867 60 I860.., 32 1868 55 Modes of Occurrence. The crevices, veins and caverns in which the lead ore is found, are all, perhaps, cracks of shrinkage, into which the lead subsequently became deposited. The most common and widely disseminated form in which lead ore occurs, is known among miners as "float mineral." In many places the beds of red ferruginous and ochery clay have scattered through them galena in considerable quantities. It is generally found in small, irregularly- shaped pieces ; sometimes in small grains, and sometimes in good sized crystals and chunks. Although widespread in its. occurrence, no heavy bodies of mineral are found as float mineral. This form of mineral deposit results from the decomposition of the overlying JO DAVIESS COUNTY. 47 Galena limestone, and in many cases it has settled down almost in the exact spot where the rock containing it once existed. The mineral in the rocks occurs in what is known as "gash veins," and takes the forms of cog, dice, chunk, sheet, float, or fibrous mineral, as modified by circumstances. The predominant forms of deposit are the vertical crevices, and their modifications into the flat sheet and flat sheet openings. A crevice is a perpendicular or nearly perpendicular opening in the rocks, of varying width and depth. When filled with galena, the deposit is called "sheet mineral." The sheet varies in thickness, from a mere seam the thickness of a knife blade, up to three inches or more in thickness. The vertical crevices have a certain well-marked parallelism to each other, and an approximate north and south and east and west direction. The east and west are, by far, the most fully developed, and -contain, by far, the largest deposits of mineral. These crevices are known by the various names of "leads," "lodes," "cracks," "veins," "ranges," and "diggings." The predominant form of mining in this county is that of the working of the vertical crevices. These are, by far, the most productive, and are characteristic of the upper and middle of the Galena limestone. The modifications of the vertical crevice are the crevice opening, pocket opening, chimney opening, and cave opening. They are all produced by the same causes. The crevice opening is an expansion of the crevice to the width of several feet in some instances ; the cavity is often filled with red ocher and ferruginous clays, intermixed with loose stones and heavy masses of galena. The pocket openings are a succession of irregularly- shaped small openings in the crevices ; the chimney opening is a rather large expansion of the crevice, extending upward to a point resembling a chimney ; and the cave opening is a large crevice opening, widening out into cave-like proportions, floored often with stratified clays. In these openings the galena is found lying over the bottom, mixed with the materials with which they are filled, crystallized in blocks or cubes over the walls, and hanging pendant from the roof. Some of the masses of mineral weigh thousands of pounds, and it is said one mass was found in the mines of Captain Harris, weighing half a million of pounds, and worth thirty-five thousand dollars. These various openings are caused by the decay or disintegration of the rock on the sides of the crevices, owing to chemical agencies working round the mineral deposits. If the dirt remains where it was formed, the mineral and nodular masses of the rock will be found embedded in it ; sometimes the dirt has been removed and the lead alone remains. Sometimes these openings extend to the surface 48 ECONOMICAL GEOLOGY OF ILLINOIS. clays ; sometimes they are covered by a cap rock. They often extend into the flint strata, characteristic of the middle and lower portions of the Galena limestone. There is often several crevices, or sets of these various openings, one over the other ; often three ; some- times as many as five ; but one opening or set of openings is usually larger than the others, and contains the heaviest bodies of mineral. The flat sheets or flat sheet openings are similar to the vertical, both as to themselves and their modifications, except that they lay flat in the rocks, parallel to their stratification, instead of standing upright. The saddle-shaped openings and pitching openings are but the transition openings from the vertical to the flat. These flat openings are characteristic of the lower parts of the Galena lime- stone and of the underlying Blue and Buff limestones, and are not found extensively developed in JoDaviess county. The "green" or "calico" rock, below the flint beds; the "brown rock," and the "glass rock," are characteristic of the lower Galena limestone, their beds of passage into the Blue, and the Blue itself. In these occur the pipe clay openings ; and in the Buff limestone the "lower pipe clay opening" is found. These are flat openings, filled with shaly limestone and a peculiar clay, from which they take their name. These lower flat openings are also peculiar in having more of the associate mineral deposits, such as tiff, blende, the ores of zinc, etc., than the upper vertical openings. In this connection I do not intend to say much as to the origin of the lead ore in the Northwest, nor to speak of the various theories as to the origin and deposition of mineral deposits in general. The question as to the origin of our lead is unsettled, perhaps. J. D. WHITNEY, the best living authority on the Galena lead basin, believes the galena and its associate minerals were deposited in the aqueous or humid way in the crevices of the rocks, and that the veins were filled from above^downwards. This theory supposes that the metals were held in solution in the waters of the primal ocean, in the form of sulphates, and were deposited in crystalline forms in the shape of the sulphurets. The decomposition of organic vege- table or animal matter throws off a sulphuretted hydrogen gas, which, acting upon solutions containing sulphates, is supposed to cause a reduction and precipitation of the metals in the form of sulphurets. The decay of sea plants and the abundance of organic life in the Trenton Period, is thought to have been sufficient to pro- duce the great precipitation of lead ore found in these rocks. The writer argues his theory with ability, and it may now be considered as the one generally received. I hazard the suggestion, however, JO DAVIKSS COUNTY. 49 that electrical action may have had much to do with the precipi- tation, crystallization and arrangement of these minerals. Early and Recent Mining Processes. The primitive mining pro- cesses in the Galena lead basin were of a very simple character. Two men selected the spot where they wished to try their fortunes. They were generally guided by certain signs in making the selec- tion, such as depressions in the ground, unusual luxuriance in the growth of vegetation, color of the clay, or ravines supposed to in- dicate crevices in the rocks below. A shaft was sunk through the clay, and cribbed by building up timber, until the rock was struck. A rude windlass, bucket and rope, a few shovels, picks and pieces of tallow candle, constituted all the tools needed, to which was sometimes added a few blasting tools. If a crevice was struck it was followed down, and drifts were driven from it in various direc- tions. The man at the top laboriously hoisted with his windlass the material necessary to be removed. The digging was abandoned when worked down to the water, or a pump is put on driven by horse-power. The mineral is brought to the bottom, of the shaft or rude car, running on wooden rails. Instead of sinking a shaft, an inclined plane or drift is run into the hill, in case the outcrops of the rock show lead crevices. If a heavy body of mineral is found at any considerable depth, a whim is put on. This is a large wooden wheel, or barrel, revolving at some height above the ground, propelled by horse-power, and containing coils of a strong rope, to which is attached rude cars or tubs, so arranged in many instances that one goes down as the other comes up. With the whim and horse-power pump, a range can be .worked considerably below the water level. Most of the prospecting and much of the mining has been done over the lead district in this rude way. It has proved very effective, and will be resorted to for a long time to come, both for prospecting and shallow mining. Gradually, however, more ad- vanced and scientific processes of mining were resorted to. Costly plants of machinery, including steam engines and expensive pumps and mining tools, were put to work in the heavier mines, especially where it was desirable to work below the water level. Prospecting is also now done to some extent by driving adit levels, so as to cut and prove all the parallel ranges in a hill or group of diggings by one level. The level also sometimes drains a large group of mines to a lower depth than could have been worked before the level was carried into the hill. 4 50 ECONOMICAL GEOLOGY OF ILLINOIS. The first attempts at smelting were also quite rude. The Indian squaws smelted the ore by roasting it in a rude stone furnace, in which they were able to melt out but a small portion of the lead. The log furnace succeeded this when the white men began to work the mines. In these some large logs were rolled into an area in- closed on three sides by low stone walls. Upon the logs fuel and ore was piled alternately to the top of "the walls. The fuel was kindled and the "charge" melted, the flowing molten lead finding its way in fiery streams to some place prepared for its reception. It took nearly a whole day to melt one of these charges, and not much more than half the lead contained in the ore was smelted out. A "reverberatory furnace," in which the ore was melted in an oven, where the blaze passed over and through the charge, was next tried, and was a great improvement in smelting processes. But they have all been superseded of late years by the Scotch Hearth, or Blast Furnace, now universally used throughout the lead region. It consists of a cast-iron box, shallow and open at top, and about two feet long and less than two feet wide. In the side and near the bottom of this box is a hole into which the nozzle of a strong bellows is placed. The bellows is generally run by water- power. A huge chimney is built over the hearth, resembling a cooper's chimney. The following detailed description of the Scotch Hearth is taken from an article in "Harper's Magazine," and is un- derstood to be the production of a lady of Galena, whose name I do not know: The hearth "consists of a box of cast-iron, two feet square, one foot high, open at top, with the sides and bottom two inches thick. To the top of the front edge is affixed a sloping shelf or hearth called the work stone, used for spreading the materials of the 'charge' upon, as occasionally becomes necessary during smelting, and also for the excess of molten lead to flow down. For the latter purpose, a groove one-half an inch deep and an inch wide runs diagonally across the work stone. A ledge, one inch in thickness and height, surrounds the workstone on all sides except that towards the sole of the furnace. The hearth slopes from behind forward, and imme- diately below the front edge of it is placed the receptacle or 'melting pot.' An inch from the bottom, in the posterior side of the box, is a hole two inches in diameter, through which the current or 'blast' of air is blown from the bellows. "The r furnace is built under an immense chimney thirty to thirty- five feet high, and ten feet wide at its base. Behind the base of the chimney is the bellows, which is propelled by a water-wheel, the JO DAVIESS COUNTY. 51 tuyere, or point of the bellows, entering at the hole in the back of the box. The fuel, which consists of light wood, coke and charcoal, is thrown in against the tuyere and kindled, and the ore is placed upon the fuel to the top of the box. The blast of air in the rear keeps the fire burning, and as the reservoir or ,box is filled with molten lead the excess flows down the grooved hearth into the 'melt- ing pot,' under which a gentle fire is kept, and the lead is ladled from it into the molds as is convenient. Before adding a new 'charge' the blast is turned off, the 'charge' already in is turned forward upon the work stone, more fuel is cast in, and the 'charge' is thrown back with the addition of fresh ore upon the wood. The combustion of the sulphur in the ore produces a large amount of the heat required for smelting. The furnace is thus kept in operation sixteen hours out of the twenty-four. "The ore is of different degrees of purity, but the purest galena does not yield on an average over sixty-eight per cent, of lead from the first process of -smelting. The gray slag is very valuable, though the lead procured from it is harder than that of the first smelting. There is left about 75,000 of gray slag from each 1,000,000 pounds of ore. The slag furnace is erected under the same roof with the Scotch Hearth, and has a chimney of its own a few feet from that of the hearth, and the 'blast' is secured from the same water-power by an additional blast-pipe driven by the same wheel. It consists of a much larger reservoir, built of limestone, cemented and lined with clay, with a cast-iron door in front, heavily barred with iron. It will burn out so as to require repairs in about three months. Open at the top, the slag and fuel are thrown in promiscuously. Under the iron door is an escape for the lead and 'black slag.' In front of this escape and below it is the 'slag-pot.' It is an oblong iron basin about a foot in depth, with about one-third of its length partitioned off to receive the lead, which sinks as it escapes, while the slag, being lighter, flows in a flame-colored stream forward, and falls into a reservoir that is partly filled with water, which cools the slag as it is plunged therein. As the reservoir fills, a workman shovels the scoriae into a hand-barrow and wheels it off. This scoriae is black slag, and worthless, the lead having now been entirely extracted. The smelter now and then throws a shovel-full of gray slag into the furnace, which casts up beautiful parti-colored flames, while the strong sulphurous odor, the red-hot stream of slag, with the vapor arising from the tub wherein the hissing slag is plunged, the sooty smelters, and the hot air of the furnace-room, suggest a thought of the infernal regions. Outside, the wealth of 'pigs,' not in the least 52 ECONOMICAL GEOLOGY OF ILLINOIS. porcine, gives one a sort of covetous desire that, if indulged in, we are taught leads directly to said regions. The Scotch Hearth requires less fuel than any other furnace. It 'blows out' in from six to twelve hours, while the Drummond furnace was kept in operation night and day." After examining the process of smelting, I concluded the above description could hardly be improved on, and hence give it a place in this report. The Future. The future of the lead region deserves a passing thought. It is an interesting inquiry as to how extensively the mines will be worked hereafter, and how nearly the supply of lead ore is now from becoming exhausted. That the present mines are far from being exhausted is well known. Many are temporarily abandoned on account of water. These will doubtless be worked extensively hereafter by heavy capitalists and companies, who will be able to put steam pumps on, and thus conquer the difficulties in the way of making them remunerative. Deeper and more scientific mining will be carried on in the future, and new mines and heavy bodies of mineral will yet be discovered. It is a fact, that not much over a tenth of the supposed productive lead district has yet been pros- pected. In all human probability, when these unexplored lead re- gions have been thoroughly and scientifically examined, other heavy bodies of mineral will be discovered. Science has already done an important work in the lead basin, and made many valuable sug- gestions, which the practical miner is now willing to avail himself of. Science has yet a great work to do, taking capital by the hand and exploring this lead field in search of hidden treasures yet locked in the bosom of the earth. It is the opinion of many practical miners and amateur geologists, that labor in the lead field will now pay more uniformly and better than in any past period of its history, and that an intelligent expenditure of capital in this direction is one of the very best investments. The Romance of Mining. Lead mining, like all other mining, is attended with hazard and uncertainty. The instances are numerous where poor, hard-working miners have suddenly found themselves in possession of a vast fortune. Indeed this phase of lead mining is so common that it hardly excites comment in the localities where it occurs. The case of the purchase and discovery of the Marsden mine is an illustration in point. The history of Mr. Champion's twenty-five years of persevering labor in running a certain adit level until he had bankrupted himself and almost bankrupted some of his generous friends, to be at last rewarded with a magnificent for- JO DAVIESS COUNTY. 53 tune, is one example of a numerous class of cases. The instances where workmen have slowly and laboriously sunk their shafts and run their drifts through the solid rock and finally abandoned the enterprise into the hands of some new man, whose very first efforts struck the "discovery" which the former proprietor had just missed, are by no means rare. Instances of hope long deferred until the heart was made sick, to be at last elated with the looked-for dis- covery, are numerous enough to make a book. The hazards, the expectations, the disappointments, the persever- ance, if fully written out, would contain much that is wonderful and even romantic. The unwritten history of almost- every great mine in the lead region would have in it some chapter of romance, some story illustrating some phase of human character. Gold mining has its wonders and wonderful effects on the human mind; the finding of wonderful oil deposits has been the cause of some curious chapters in human history ; lead mining, where sudden for- tunes have been poured into the laps of those unused to fortunes, or where steady, persevering toil," with its high faith in its own un- yielding endeavors, has at last been rewarded in the most ample manner, has its curious chapters bordering upon the romantic. The story of unrequited labor must sometimes be written in writing the history of the mines ; but far oftener the historian of the lead mines may record that steady persevering effort hardly ever fails at last in obtaining its rich reward. In addition to my own observations upon the geology of this county, I take pleasure in acknowledging valuable aid derived from Mr. Houghton's pamphlet on the Marsden Mine, D. Wilmot Scott's little business directory of the county, the copy of "Harper's Monthly" above referred to, and suggestions obtained from Captain E. H. Beebe, of Galena, and Dr. Little and Henry Green, Esq., of Elizabeth. CHAPTEK III. STEPHENSON COUNTY. This county is bounded on the east by Winnebago, on the south by Ogle and Carroll, on the West by JoDaviess, and on the north by Green county in the State of Wisconsin. It thus lies in the northern tier of counties in the State, and is the second county eastward from the Mississippi river. It is twenty-seven miles wide, from east to west, and about twenty-one and a quarter miles from its northern to its southern boundary line; and contains about five hundred and seventy-three square miles. The northern part of the county, according to surveys made by the Illinois Central Eailroad Company, averages about seven hundred and twenty-three feet above the level of the Mississippi river at Cairo, about four hundred and fifteen feet above the level of Lake Michigan, and about one thous- and feet above the level of the sea. The southern part of the county averages some two hundred and fifty feet lower than these figures. The general level of the county, it will thus be seen, pre- sents a gentle slope to southern, sunny skies. The general surface or face of the county is composed of gently undulating and rather rolling prairie land, interspersed with small groves, and narrow belts of timber land skirting the streams. A small portion of the county is made up of barrens and oak orchards or openings. The prairie soil is of unsurpassed fertility, and under a high state of cultivation and improvement. It is not so black and deep as the prairie soil further south ; but is drier, sandier; lighter or more chocolate-colored, producing in great perfection all the staple crops of the northern part of the State. The oak openings and other poorer portions of the county produce the best wheat and other cereal grains, the best potatoes raised in the State, very excellent apples, and pears of the hardier varieties, and with proper care and cultivation will nourish STEPHENSON COUNTY. 55 the vine and ripen its fruitage to a greater extent than is now dreamed of by the grape growers and wine makers of the West. Indeed, the day is coming, in our opinion, when its gravelly hills and .Loess clays will not only blush with the purple clusters of such vines as best endure our cold climate, but will also become sources of profit to their cultivators and sources of exquisite pleasure to those who delight in using healthful, invigorating, pure wines. The soil of this county, as of all these northern counties, also produces and ripens in great perfection, the currant, gooseberry, strawberry, raspberry and other garden fruits. The county is reasonably well watered with streams, which flow in various directions over its surface. Of these, the Pecatonica river is the largest and most important. It enters the county about seven miles from its northwest corner, flows in a course a little south of east to Freeport, bends round to the westward at this latter place, and enters the county of Winnebago, not far from the center of its western boundary line. Its waters are turbid, and muddy as the "Yellow Tiber;'' its course is serpentine and crooked beyond com- parison, winding and doubling upon itself in the most capricious manner; its current slow flowing, treacherous and silent, notwith- standing the general difference in level between the northern and southern portions of the county, affording few water powers, and they of limited fall, but heavy and constant in their action. This is pre-eminently true of the six feet fall at Freeport, but hardly so true of the power at Martin's mill, just across the northern line of the county. Indeed, so far as a description of the stream is con- cerned, the dispute as to the Indian significance of the name Peca- tonica "muddy water" and "crooked stream" might be well recon- ciled by adopting both meanings and applying them with much truth to this tortuous body of flowing mud. Along portions of its course, its oozy banks and stagnant waters might breed miasms and fevers, were its influences not counteracted by the general health- fulness and salubrity of the climate of Northern Illinois. Yellow creek enters the county almost at the center of the western bound- ary line, and flows into the Pecatonica two or three miles below and east of Freeport, its general course being a little south of east. Its waters have a yellowish, somewhat creamy color, and are slow flowing like the Pecatonica. The color of its water is derived from the Cincinnati shales, along its banks, which dissolve and mingle with the water like yellow cream with muddy coffee. Its course is not so crooked as the stream with which we are comparing it. It wanders about in long undulating curves, instead of short, abrupt 56 ECONOMICAL GEOLOGY OF ILLINOIS. doublings. It affords few water powers, and they of limited extent. Cedar and Eichland creeks rise almost entirely within the county towards its northern and central parts, flow southward, mingle their waters together within a few miles of the Pecatonica, and empty into the latter stream a few miles above Freeport. Both these streams afford light, but rather constant water powers. The mills of the Hon. John H. Addams are located upon the former, at the romantic little village of Cedarville; the Sciota mills are located upon the latter, after its union with the former. Both these streams have bright, clear waters. They are not mountain born, but are fed by prairie and woodland springs, almost entirely within the bound- aries of the county lines. Bock run enters the county, about four miles from its northeast corner, and empties, after running about twelve miles on an air line, into the Pecatonica about one and a half miles west of where it crosses the western line of Winnebago county. This is a beautiful little stream, affording a very few light, and not very valuable water powers. It goes babbling and mur- muring along through rich prairie farms and woodland groves, until within a dozen miles of its mouth. Here the banks rise to a pre- cipitous, brush-covered, timber- crowned hill, and in a few miles further the low alluvial bottom of the Pecatonica is entered, through which it seeks its way with less haste into the dirty waters of the latter stream. Crane's creek is a small and short prairie stream or brook, flowing into the Yellow creek, nearly south of Freeport, com- ing in from near the center of the southern boundary line of the county. Besides these there are many brooks, rivulets and little streams in various parts of the county, watering it reasonably well both for agricultural and stock raising purposes. Nor should we omit to mention, in this place, the bright, flashing, singing little Silver creek, which runs northward through the town of the same name, and finds its way into Yellow creek, not far from its mouth. In comparison with most of our northern counties, Stephenson might be said to be well timbered. The Pecatonica is skirted, more especially along its eastern bank, with a body of rather heavy timber, spreading out northward into the town of Oneco for a con- siderable distance. Y'ellow creek is fringed, for a part of its course, with a scattering growth of white oak groves and clumps, spreading across from Mill Grove towards Eleroy and the Sciota mills into oak openings and a somewhat rough soil. Part of the town of Loran, in the southwest part of the county, is a regular white oak barren, with 'scattering trees and some brushwood. Crane's grove, lying south of Freeport, is about three miles long and more than a mile STEPHENSON COUNTY. 57 wide. Lynn and walnut groves dot the broad expanse of prairie in the northeastern part of the county, with a grateful change in the monotony of the prairie view. Cedar creek has some good timber along its course. Eichland creek is shadowed by the heaviest body of good timber perhaps in the whole county. The prevailing timber consists of white, black and burr oak, sugar maple, black walnut, butternut, pignut, shell-bark and common hickory, slippery and water elm, yellow poplar, with occasional laurel, red cedar, white pine, paw-paw, and some of the rarer oaks, interspersed. Sumach and hazel also abound in and around all the groves. Wild cherry, honey locust, linden or basswood, ash, cottonwood, sycamore, and some other varieties of timber, are more or less to be noticed, and in some particular localities are found in considerable abundance. Such, in brief, are the topographical features of Stephenson county a county whose agricultural resources are not surpassed by those of any county in Northern Illinois. Indeed, it would be hard to find an equal area anywhere in the State whose soil is so uni- versally good, productive and teeming in every bountiful gift to the industrious tillers of the earth. No mineral wealth or peculiar manufacturing facilities will attract to this county the attention of the adventurous ; but for those resources which are derived from a rich soil and abundant agricultural capabilities, this favored county may well claim a lastimg pre-eminence. Geological Formations. The geology of Stephenson county is of very simple character. After leaving the surface geology, the first formation met in a de- scending order is the Niagara limestone, succeeded in regular order by the Cincinnati shales, and the three divisions of the Trenton period, namely, the Galena, Blue and Buff limestones of the old Trenton seas. The following section shows the actual worked exposures of these rocks as measured in the quarries by the writer of this article. In no instance, perhaps, do the measurements exhibit the maximum thickness of the formations. At some points where measurements' were made the rocks of the formations meas- ured undoubtedly extended downwards to an indefinite extent, and in a few particular instances, where the bottom of a formation was distinctly identified, denuding agencies had carried away much of the superincuml>ent mass. A section thus constructed might be 58 ECONOMICAL GEOLOGY OF ILLINOIS. styled a surface section of the formations indicated, and in a level country, where no borings had been made, would be the only attainable one to be had. Section of Worked Outcrops. Feet. Quaternary deposits, consisting of clays, sands, gravels, surface soils, etc 10 to 65 Niagara limestone 23 Cincinnati group 40 Galena limestone 75 Blue limestone 38 Buff limestone 40 Each of these groups or formations outcrops at some place or places in the county. Some of them are the immediate underlying rocks over large portions of the same. As further illustrating the geological formations of this county, and more especially those which lie deep down in the earth, we now give an imperfect section, obtained from the borings of the rocky farm oil well. This well was commenced, we believe, in 1864, and continued on through a greater part of the year 1865. At that time the oil fever was prevailing extensively. Some surface indications were noticed in a small brook running through the north part of section 6, in the town of Lancaster. A company was formed, an engine was obtained, and a hole six inches in diameter drilled into the earth for over eight hundred feet. No oil was obtained, and no indications of oil noticed after leaving the surface, and the enter- prise was finally abandoned. Although very unprofitable to the company, this boring was not devoid of scientific interest. After boring about eight feet through the overlying soil and clays, the Galena limestone was struck. No very accurate record of the material passed through for the first one hundred and twenty feet was kept, but from the fact that the Galena limestone outcrops heavily at Cedarville, only a mile or two distant, being- there seventy- five or eighty feet thick in the exposure on Cedar creek, we believe the well, in this one hundred and twenty feet, passed out of the Galena limestone, and reached perhaps a considerable distance into the Blue limestones, immediately underlying. Commencing at one hundred and twenty feet beneath the surface, we give a section of strata and materials bored through, until the depth of six hundred and eight feet was reached, as indicated by the detritus brought to the surface by the auger. No record of the last two hundred and fifty feet seems to have been kept. STEPHENSON COUNTY. 59 Section of Oil Well on Rocky Farm. Feet. Feet. 120 to 130, blue limestone and mud veins 10 130 to 146, gray limestone, containing crevices I 6 146 to 168, shales of various kinds 22 168 to 375, St. Peters sandstone, soft, very white 207 375 to 484, red sandstone, with tough, paint-like mud veins 109 484 iff 487, yellow sand, like surface sand 3 487 to 491, quicksaad and salty water 4 491 to 494, bright-yellow, fine, salty sand 3 494 to 501, slate of chalky color and nature , 7 501 to 520, snuff-colored, slaty rocks 19 520 to 532, sharp, slate-colored sand 12 532 to 564, dark-red stone, like soapstone. with thin, flinty strata and iron pyrites 32 564 to 586, bright-red stone, slightly oily 22 586 to 608, dark, reddish slate, with iron pyrites 22 At the depth of about sixty feet from the surface some dark- colored carboniferous shales were struck. These must have belonged to the Blue limestones underlying the Galena, and perhaps are near the dividing line between the two. From thence, to the depth of one hundred and sixty-eight feet, the Blue and Buff limestones of the Trenton period were undoubtedly the rocks passed through. The next two hundred and seven feet was the St. Peters sandstone. There could be no mistake as to this; the auger brought it up, pure, crumbly and white. The next one hundred and nine feet, although it strongly resembles the St. Peters sandstone when stained by water holding iron in solution, belongs, perhaps, to the Calcifer- ous sandstone, or lower Magnesian limestone of the Northwest. The next one hundred and twenty-four feet almost loses its identity, but perhaps belongs to the lower Calciferous sandstone and to the Pots- dam sandstone. Chemical analysis of the materials brought to the surface, aided by a strong magnifying glass, may show these sur- mises to be partially untrue. We admit they are little better than scientific guesses after studying the above section, and examining with the naked eye and the touch specimens of the abraded ma- terials, preserved as brought up by the drill. We have attached some importance to the above section, because it is a matter of much interest to the citizens of Stephenson county, and because it afforded to the writer the only opportunity he had, in all the country examined the past summer, of making even a partial examination of the deep, underlying formations. It also set- tled another question then agitating the public mind in this part of the State. Before this experiment, geological science had foretold that no productive oil deposits would or could be found in this part of the country. It had predicted this from knowledge of the underlying strata, and their inability to collect and preserve the oily treasures of the earth. But capitalists lacked faith in the teachings 60 ECONOMICAL GEOLOGY OF ILLINOIS. of science, and acquired in the school of experience the lessons which they would nowhere else learn. The experiment of this well had a wonderful influence in allaying the oil fever in this region. We cannot leave this subject without rendering our acknowledg- ments to F. E. Dakin, Esq., of Freeport, to whom we are indebted for the figures in the above section, and also for small and care- fully labeled specimens of the materials brought to the surface, dur- ing every ten feet of the distance to which the well was sunk. We shall now proceed to describe, in detail, these outcropping geological formations. Quaternary Deposits. These deposits cover unconformably the underlying rocks to a varying depth. At some places they are five or ten feet thick ; at others they perhaps extend in thickness to sixty or seventy feet. To say that they average twenty-five or thirty feet all over the county, would, perhaps, be placing the figures safely within the bounds of truth. If all this accumulation of deposited materials could be removed, the surface of the underlying rocks would present a very rough, uneven surface. Scooped out depres- sions, extending through overlying formations and over large por- tions of the country, presenting, if filled with water, the phenomena of broad, shallow lakes, would be seen. The mounds, rising like watch towers over these prairies (resisting, on account of some local cause or hardness, the denuding agencies that carried away the rest of the formation), would appear like islands in the surrounding waste of waters. The rocky surface thus left, so far as we can judge from the limited examinations we are now able to give that surface, would be unsmoothed by water current and unscratched by glacier, but would be everywhere uneven, rough, and covered with unworn fragments of stone. Along the narrow bottoms of the Pecatonica may be noticed a strip of Alluvium proper. At some places it is very narrow, at others it extends to one or two miles in width. The same deposit may be observed at a few localities along the Yellow creek bottom, and also along the narrow bottoms of some of the smaller streams. The deposit, however, is of limited extent; it is rich, fat, and heavy as an agricultural and timber soil. Along some of these streams the low, bald hills are found to be composed of the Loess marls and clays ; but this deposit is also of quite limited extent in the county. All the rest of these superficial deposits belong to the sands, clays and gravels of the Drift proper. These clays and clayey sands, how- ever, do not furnish very strongly the evidences of deposition or transportation. They seem to partake, in part at least, of the nature STEPHENSON COUNTY. 61 and character of the rock formations lying immediately below them. In every instance examined, this seemed to be true. Where the Galena limestone is the underlying rock, the appearance was some- what as follows : First, there was the prairie soil and clayey sub- soil, at most only a few feet in thickness ; this was succeeded by a reddish-brown clay, mixed with flints and pieces of cherty Galena limestone ; then came the clay and pieces of the limestone preserv- ing their regular stratification, the limestone becoming more abundant in the descent, until the solid rocky strata was reached. In a few instances this overlying clay is creamy in color, and almost limey in texture; but the prevailing color is reddish-brown or red, and in many cases it is more or less mixed with sand. The clays overlying the Cincinnati shales also bear a resemblance to this formation, from which they are doubtless in part derived. They are of creamy or more chocolate color, finer in texture and freer from sand. These superficial clays and loams certainly have the appearance of being the residuum left after frost and water had pulverized, and, by per- colation, removed the more soluble portions of the uppermost parts of the formations below. But, aside from these deposits, the gravel beds and boulders of the true Drift period are not wanting in this county. That part lying west of the Illinois Central railroad and south of Yellow creek being mostly low, level prairie, underlaid mostly by the Cincinnati shales, and also that low, rich, level part between Waddam's Mound and the range of mounds running from the neighborhood of Warren towards the southwest, and underlaid by the Galena limestone may almost be denominated a driftless region. Few boulders are seen over it, and few or no real gravel deposits can be found. The prai- ries north and east of Waddam's Grove have strewed over them numberless boulders, some black, some flame-colored, and some com- bining the various colors of the metamorphic rocks. At one place, about half way between Waddam's Grove and Winslow, they are rolled into wind-rows along the road, and used in part for the lane fences. Many of these are exceedingly beautiful, and many colored. They are the real "lost rocks," and must have been dropped from the slow-moving icebergs, as they drifted along towards the south- west. All that part of the county north and east of the Pecatonica is characterized by these boulders, and by many deposits of gravel and gravelly clays, to be met in almost any of the low ridges of land. The same may be said of the eastern portion of the county, excepting that the deposits are not so extensive. 62 ECONOMICAL GEOLOGY OF ILLINOIS. Some other formations belonging to the surface geology, such as fire-clay, peat, bog-iron ore, muck, and the like, will be referred to when we come to speak of the economical geology of the county. The Niagara Limestone. The superficial extent of the county cov- ered by this formation is quite small. Waddam's Grove, quite a high elevation of land, two or three miles long and a mile or two wide, and located a little northwest of the town of Lena, is capped by the Niagara limestone. At French's quarry, near the top end of this elevation, facing towards Lena, there is an exposure worked to the depth of about fifteen feet. French's well, near the same spot, is forty-five feet deep, the upper twenty feet being sunk through this formation, and the lower twenty-fire feet sinking into the underlying Cincinnati shales. At Blakesley's quarry, twenty-five feet of the same formation is worked into. This is about one mile west of French's, on the north face of the hill. Here they have worked down to the Cincinnati shales. The bottom layers in both these quarries are compact and solid; the top layers are thick, irregular, speckled and porous. A species of slender, rotten Cyaihophyllum was the only fossil observed in these quarries. From the latter quarry the prospect towards the north and west is beautiful beyond description. The low, level, rich prairie, with its fields and mead- ows, barns and farm houses, skirted in the distance by the range of mounds, bending around like a distant amphitheatre into JoDa- viess county, presents as fine a prospect, beneath a glowing June sun, as we ever beheld in any State. Leaving this elevation, we next find the Niagara outcropping in the southwestern part of the county. We would indicate its extent by a line, which should enter the, county from the'west in the town of Kent, some three miles south of Simmons' Mound, and then fol- low the' general course of Yellow creek, keeping distant from that stream from two to five miles, until nearly opposite to Crane's Grove, then carried southward until the south boundary line of the county was reached, near its bisection by the Illinois Central rail- road track. This line would cut off that part of the county under- laid by the Niagara rocks. And even in this, some of the small streams which come into Yellow creek through this section cut into the Cincinnati group, and a band of the Cincinnati group, along Lashell's Hollow, where the little village of Loran is located, also discloses the shales and quarries of this group. We would change Professor WHITNEY'S map of this part of Stephenson county, to be found in the first volume of the original Keports, so as to make the green ribbon or band south of Yellow creek, denoting the Cincinnati STEPHENSON COUNTY. 63 rocks, very much broader, and the color denoting the Niagara rocks very much less. This formation is not much quarried in this part of the county. At Big Springs, in Lashell Hollow, quite a quantity of stone have been taken out. Few fossils were observed, except that great quantities of some of the rougher Niagara corals lie strewn over the hills about Loran, consisting of two or three species of Favosites, and some imperfect Haly sites. Cincinnati Group. The rocks and shales of this group cover but a limited extent of this county. All that part of Waddam's Grove between the level of the surrounding prairie and the capping Niag- ara, is composed of the shales and rocks of this group. The gentle slopes of the ascent, and the creamy-colored waters from the springs, ' are an unfailing index of this formation. No quarries are opened in it, but it is here, perhaps, forty feet thick. The broad belt south of Yellow creek, crossing this stream in the township of Kent, ex- tending up into the southwest corner of the township of West Point, as indicated on the general map, has been referred to sufficiently, perhaps, in speaking of the previous formation. About the village of Loran, the hills on either side of the creek, to their top, are com- posed of the Cincinnati rocks and shales. Many quarries are opened in the face of the hills, and fair building stone are obtained. The worked outcrops here are fifteen or twenty feet thick. As we follow the creek to the northward from here a few miles, the Cincinnati formation runs under, and the Niagara takes its place. In the half township of Erin, just west of the village of Eleroy, there is quite an elevation of land, covering several sections, and crowned with a scattering grove, which is made up exclusively of the Cincinnati formation. On the west end, at the little village of New Dublin, there is a quarried outcrop some forty feet deep. A Catholic chapel is built out of stones from this quarry. It seems to be enduring the influences of the weather reasonably well. Although quite as high as Waddam's Grove, we did not detect any overcapping Niagara on this elevation. A bold and steep escarpment on the north side, caused by extensive quarrying, can be discerned from a long distance off, and is a marked feature in the landscape. The rocks here pre- sent a dry and baked appearance. Hardly a trace of a fossil could be seen. An accident here, to our pocket level, prevented an ac- curate measurement of this interesting mound. Crane's Grove, com- mencing about one mile north of Baileyville, and extending over several sections towards the northwest, is another of those elevations, left standing when the surrounding formation of the Cincinnati group was eroded and carried away. The worked outcrop near Baileyville, 64 ECONOMICAL GEOLOGY OF ILLINOIS. furnishes stone fit for ordinary foundation purposes, but entirely un- fossiliferous. East of the Illinois Central railroad track, in the town- ship of Silver Creek, some isolated patches of the Cincinnati shales and clays may be noticed, but the formation in this direction soon gives place to the Galena limestone. These quarries of the Cincinnati group afforded few fossils. In the little streams and on the hills about Loran, the Orthis testudinaria and Orthis occidentalis may be found in some abundance ; but we have yet to find a Cincinnati quarry, except along the Mississippi river, abounding in even characteristic fossils. The Trenton Limestone. This formation, as now recognized by geologists, embraces the Galena, the Trenton proper or Blue, and the Buff limestone. These divisions are well marked and easily distinguishable, and in these reports we shall describe and refer to them by these well-known names. The Galena Limestone. Nearly three-fourths of Stephenson county is underlaid by this well-known division of the Trenton rocks. And inasmuch as the railroad cuts and the streams afford the best facili- ties to study the geologic formations of these counties, we shall first pass along them in our description of this wide extended member of the group. The Illinois Central railroad enters the county at Warren, near its northwestern corner. It passes over a low, smooth prairie, without outcrop or stone quarry, to Lena. Waddam's Grove, which stands in this prairie, shows that the Galena limestone under- lies it. At Lena there is a quarry and a lime-kiln within a short distance of the town, exposing some fifteen feet in thickness. In about two miles further there is another. Both are on a little stream towards the north. Passing .on towards the southeast the railroad exhibits several small sections in the top of the Galena beds, but does not afford any heavy section, until Freeport is reached. Just west of the city, along the track of the railroad, and near the banks of the Pecatonica river, in a low range of hills, three extensive quarries are worked, furnishing stone for lime, and for the large amount of building material needed. The first, nearest the city, is worked about eighteen feet deep. The rock obtained here is very soft, yellow, sandy, and full of cavities the size of a walnut. Where heaps of it have been removed, a considerable amount of sand is left scattered on the ground. The top layers of this quarry are so friable and crumbling, that hand specimens will hardly remain in shape. The second quarry exposes an outcrop of about twenty- four feet. The third is exactly similar to the second. Both of them are somewhat shaly towards the top, but rapidly grow massive and STEPHENSON COUNTY. 65 solid as they are worked into. These three quarries are within a short distance of each other. A few feet of reddish clay, with small stones intermingled, covers the strata where these quarries are opened. These are the last outcrops upon the Illinois Central rail- road. The Western Union railroad enters the county on a line almost exactly south of Freeport, and passes out of it about four miles south of its northeast corner. Three miles southwest of Free- port it cuts through the top of the rock under consideration, expos- ing the usual red-clay, and over this a gravelly subsoil. This cut is a small one. About three miles northwest of Freeport there is an exactly similar cut. About a mile further on towards the north- west is another, which measured one thousand feet long and twenty- four feet deep in the middle. Further on, and a little over a mile west of Rock City, is another cut three hundred and fifty yards long, and fifteen feet deep in the solid stone at the deepest place, and the stone covered by about ten feet of the usual gravelly clay. Here the stone is hard, glassy, conchoidal in fracture, and begins to assume the characteristics of the Blue or Trenton proper. One- half mile further on and nearer Rock City there is a cut about twelve feet deep, the lowest part exposing the real Blue limestone. Further on, and one mile east of Dakota, there is another cut into the Yellow Galena. The cut is not a large or important one. Fur- ther on, at the railroad bridge, over Rock run, there is a cut about twenty-two feet deep. The first five feet is the usual reddish clay; the next twelve feet is Galena limestone, assuming characteristics of the Blue, and the last five feet is into the real Blue iself. The union of the Galena and Blue, passing into each other almost imperceptibly, may be satisfactorily examined here. The next and last cut is about one-fourth of a mile east of Davis, almost on the county line. It is over one thousand feet long and about thirty-one feet deep; the upper seven feet is the usual clay, with some gravel in it ; the lower twenty-four feet is Galena limestone, solid, a little bluish in color, and of a somewhat conchoidal fracture. In fact, all these exposures along the eastern part of the county, in their blue color, conchoidal fracture, and hardness, differ considerably from the Freeport quarries. They are lower down in the series, and assimilate somewhat into the character x of the Blue below. So true is this, that in some of the exposures it is hard to fix upon the line of separation between the two. From Freeport south, along this railroad track, no other exposures of the Galena limestone are visible. 5 66 ECONOMICAL GEOLOGY OF ILLINOIS. Leaving the railroad cuts, the streams present the next best oppor- tunities to trace the superficial area, thickness and phenomena of this deposit. The Pecatonica river, about four or five miles after entering the county, strikes the Galena limestone, and for its whole distance in the county exposes this formation where any rocks are exposed along its banks. There are no very good exposures, how- ever on this stream, except those at Freeport, already referred to. At Bobtown, or New Pennsylvania, an outcrop is worked near the river ; and at or near the mouth of Yellow creek the formation is dug into in an old crevice lead mine. Richland creek and Cedar creek both expose the Galena rocks for their entire length. Both these streams have cut deep into the solid rocks, and at many places along their banks heavy outcrops and escarpments stand out in bold relief. At Buena Vista, on the former stream, there is an outcrop of twenty feet, quarried into for its whole depth. At Cedarville, on the latter stream, the outcrop is seventy-five feet thick. A large quarry is here opened, out of which the stone in Addam's mill-dam have been taken. This is one of the most romantic little places in the county. The high, rocky hills, with their green crowns of ever- green cedars, the more than Cyclopean walls of solid rock, rising along the banks of the clear, shady stream, and the neat little vil- lage, all make it a point not soon to be forgotten. At the Sciota mills, below the confluence of the two streams, and in many places in that neighborhood, the same rocks are exposed and quarried. Crane's creek, where it washes the west end of Crane's Grove, ex- poses the Galena limestone. It is here quarried for the surrounding prairie to a considerable extent. The same limestone is worked into at Rosenstiel's quarry, near Freeport, to a depth of about twenty- two feet. A hard, gravelly, red clay covers this quarry to the depth of eight feet. Bands of chert also exist in the clay and in the top layers of the stone. Leaving now the streams, we will mention some localities exam- ined in other parts of the county. Burr-oak Grove, half way between Lena and Winslow, has near its eastern limits an interesting out- crop. About two and a half miles west of the latter place, almost every little prairie hilltop is dug into, and several small quarries opened. An exposure of twenty-four feet was also examined at the lime-kiln, a little southeast of Eock City. The top of this quarry is Galena limestone, but it gradually changes into the Blue before the bottom is reached. In the township of Ridott the Galena is the underlying stone, changing into Blue towards its eastern and south- eastern part. In the township of Oneco the formation is heavily STEPHENSON COUNTY. 67 developed. In short, the outcrops of this well-known formation, or division, of the Trenton rocks, are so numerous that we do not deem it necessary to particularize them more fully, but shall briefly give the 'superficial boundaries and area, as marked upon our map of this region. All that part of the county between the Pecatonica river and Yel- low creek, except a small strip east and south of Winslow, and except the development of the Cincinnati group at Waddam's Grove, New Dublin, Kent and along the banks of the Yellow creek, is underlaid by the Galena rocks. All that part of the county north and east of the Pecatonica river, except a strip in the bed of, and along either side of Eock run, is underlaid by the same. The south- eastern part of the county, nearly up to the Pecatonica river, and nearly to the track of the Illinois Central railroad, with the excep- tion of a strip along the southeastern corner, and a few isolated patches in the eastern part of the township of Silver Creek, is also underlaid by these same rocks. Fossils. Few fossils are found in the Galena limestone in Steph- enson county. The characteristic Receptaculites Oweni, called by the miners and quarrymen "lead blossom," and "sunflower coral," ie found at Freeport and Cedarville in great abundance, but good speci- mens are hard to obtain, on account of the friable nature of the stone in which it is found. At the former place a specimen of Re- ceptaculites orbicularis was noticed. Two or three species of Murchi- sonia, fragments of several species of Orthocera, one or two well known Orthis, two species of Pleurotomaria, a small Bellerophon, and a rather well defined Ambonychia, were the fossils most usually observed. They all exist in the form of casts, and perfect cabinet specimens are hard to find. The Blue Limestone. This, the middle division of the Trenton, is of limited extent in this county. Of course, in many places marked on the map, with the color indicating the Galena, a shaft sunk down a short distance would strike the Blue limestone ; but we now de- scribe it as the surface rock, and only speak of it, where developed, as a surface rock. Rock run cuts into the Blue limestone soon after entering the county, and all along its banks, on both sides, until within a mile or two of its confluence with the Pecatonica, this rock outcrops and shows itself. Some of the high, rocky banks are over- capped with the Galena, but the usual rock is the Blue. At the railroad bridge of the Western Union Eailroad Company, over Eock run, the railroad track is about six feet below the junction of the Galena and Blue. Stepping west, out of the railroad cut, there is DO ECONOMICAL GEOLOGY OF ILLINOIS. a perpendicular descent of thirty-three feet, from the track down to the water level, making the whole thickness of the Blue at this place about thirty-nine feet. The lower part of this outcrop is very blue, the upper part yellowish, with thin strata, and gradually changing in lithological character, until the overlying Galena just east of the bridge is reached. This is a very interesting section. One and a half miles below this locality is another quarry, opened in the west bluff of the stream. The outcrop is twenty-five feet thick. The top part is shaly and yellowish ; the bottom becomes heavier and bluer in color. Some of the thin shaly strata are full of a small sized Orthis. These two outcrops are fair representatives of all the others along this stream. Leaving this stream, we find no other outcrop in the county. Some indications of underlying Blue limestones prophecy its existence in the southeastern part of the county, and we have so marked it on the map. Some slabs, with fossils similar to those found in the Dixon mar- ble, were picked up ; these, with the fragmentary stems of encrinites, were the only fossils found. A small specimen of "sunflower coral" was found in the Blue limestone, at Eock Run railroad bridge, the only one ever found by us in this rock. The Buff Limestone. The only place where this, the lower division of the Trenton, is developed in this county, is at Winslow. It is doubtless the underlying rock for a few miles below this place, and on both sides of the Pecatonica river, for this distance. Here it presents very much the appearance of a quarry in the Blue. The top is shaly, thin-bedded, and of a yellowish-chocolate color. At Mar- tin's mill, in Wisconsin, one mile above, the outcrop is much heavier, the bottom layers more massive and very blue. Professor WHITNEY pronounces these exposures outcrops of the Buff, and the fossils seem to indicate that he is correct in this. The lithological charac- ter of the quarries would indicate the same thing, but in a less satisfactory manner. On either side of this strip of Buff and within a short distance of its outcrops, the Galena limestone comes to the surface, so that the latter seems to rest unconformably upon the former; but in following the stream to the northward, a few miles above the mill, the St. Peters sandstone begins to show its outliers. The quarry at Winslow is worked twenty-three feet deep, and at Martin's mill thirty-five feet, and at both places it is some ten feet from the bottom of the quarries to the surface of the water. Geo- logically, the locality is one of the most interesting in this part of the State. STEPHENSON COUNTY. 69 Fossils. We found here many well preserved casts of fossils. Among them the most characteristic were Pleurotomaria subconica ; a large Orthoceras five or six inches in diameter, and some six feet long, with a part of the shell still wanting; a Cypricardites niota? Oncoceras pandion; some two species of Tellinomya ; and some other fossils, which will be mentioned in our catalogue of the fossils of this part of the State, in the prefatory chapter to these county re- ports. Economical Geology. The chief sources of wealth in Stephenson county are to be found in the richness and productiveness of its soil, and in its abundant agricultural resources. So far as our examinations go, this is the best agricultural county of its size in the State. It has less waste land than any other we know of. It has a larger number of acres under successful cultivation than any of its neighbors; and from this cultivation labor reaps a richer reward than California's golden mines can bestow, and as a result, unexampled prosperity attends the tillers of the soil, and through them smiles upon all other pur- suits and avocations which wait upon successful agriculture. In her fat rich soil, therefore, is contained the first and chiefest source of wealth in this county, the one which is nourishing all the rest, and fostering and building the city of Freeport in a wonderfully rapid manner. But aside from this there are other sources of wealth and industry demanding our attention. Clays and Sands. Almost anywhere beneath the soils and subsoils may be found clay beds, out of which an excellent article of common red brick can be manufactured. This is more especially true of the reddish clays overlying the Galena limestone. Beds of sand are also found, sufficiently pure for mortars and plastering purposes, but they are far less numerous than the clay beds. A tough, tenacious dark- colored fire-clay also underlies some of the peat marshes, which has been dried and baked into a tenacious light-colored brick, as an experiment, but this is not, perhaps, of much economic value. Quicklime. The more solid portions of the Galena limestone burn into a quicklime of excellent quality, and there are many lime kilns in the county. Certain portions of the Blue limestone also burn into a good lime, and at Martin's mill certain portions of the Buff are being successfully made into lime of fair quality. Building Stoyie. All the rocks hitherto described furnish building stone of better or worse qualities. The Niagara is quarried in several 70 ECONOMICAL GEOLOGY OF ILLINOIS. places. It furnishes a handsome colored enduring building material, but is unshapely and unmanageable on account of its irregular strat- ification. The Cincinnati group, although considered an unreliable building material, is much quarried about New Dublin, and in that region. It comes out of the quarry in good shape for light work, and does not crumble and decay when exposed to the weather, as we have seen it do farther to the west. Barn foundations, houses, bridge abutments and other such work may be seen built out of the Cincinnati group at many places in the western part of the county. The Catholic chapel, before alluded to, is built out of this material, and ddes not, as yet, exhibit much signs of decay. Indeed, some of the bottom strata are massive, very blue, and excessively hard ; but yet the Cincinnati group would not furnish stone suitable for massive and solid masonry, or for long continued resistance to the action of the elements. The Galena limestone furnishes a good material for the heavier kinds of masonry. It is a rough unshapely stone, re- quiring much labor to lay it, but when well dressed and laid, it seasons into great hardness, and takes a beautiful cream or chocolate color. Nearly all the stone work in the city of Freeport is built of this stone. The new Gothic Presbyterian church, just completed, at great expense, is a noble, imposing structure, whose walls were taken from the Freeport quarries. For heavy pier work this stone is un- equaled. The Blue and Buff both afford a good stone for building purposes. The upper strata are too thin and irregular, but the lower blue strata afford the most beautiful building stone to be found in this part of 'the State. The only difficulty seems to be, the great labor in quarrying, on account of the great amount of worthless materials to be removed before reaching the handsome and valuable portions of the quarries. Minerals. Some bog iron ore may be found in some of the marshes, but it is of little value and limited extent. Pieces of float copper have been found in the gravel beds, bat they are of rare occurrence, and come from regions far remote. Galena, or common lead ore, is and has been mined for, to some extent. There is an old crevice mine near the mouth of Yellow creek, that has often engaged atten- tion in years past, but no heavy amounts of mineral have ever been taken from it. From the quarries near Lena, "chunks" as large as the fist have been taken. In the township of Oneco a company of Freeport men prospected to a considerable extent, and obtained sev- eral hundred pounds of mineral. Near Wetzell's mill some "pros- pecting" has been carried on. Along the banks of Yellow creek, some "float mineral" has, been picked up; and in almost any of the STEPHENSON COUNTY. 71 quarries, small bits of the ore may be detected. But none of these localities have shown heavy bodies of lead. Indeed, the Galena limestone, notwithstanding its general prevalence in this county, seems to be very unproductive of rich bodies of mineral wealth. The probabilities are that no rich, or even good paying, diggings will ever be discovered, for the simple reason that they do not exist within the borders of the county. Small deposits undoubtedly do exist, and will occasionally create some excitement, and invite the expenditure of mining capital, but, in our opinion, capital thus spent will never make remunerative returns. Peat. At several localities peat beds of some value have been discovered. On the farm of a Mr. White, in township 26, range 9, a bed of about fifty acres exists. It is from three to six feet deep, and is underlaid by a tough, tenacious, dark-colored fire-clay; the peat is of a rather poor quality, and with our present knowledge of pre- paring fuel from this substance, is, perhaps, of no great value as a fuel. Near Lena and Burr Oak Grove, very small beds were exam- ined. On the low, level prairies south of Yellow creek, and ranging between Florence and Crane's Grove, almost every swale and marsh has in it more or less peat. One of these beds is quite extensive, and will become valuable as soon as the peat experiment succeeds. It is found in the township of Florence, between sections 25 and 26, the section line running along near its middle. It is from forty to fifty rods wide, and about one hundred and srxty rods long, containing well nigh fifty acres. About one-half of it is owned by G. Purington; the other half is owned by parties whose names we did not obtain. So far as we could obtain the depth of peat, it ran from six to about nine feet. Careful borings would, perhaps, show a greater depth. Through its center, a small stream of pure water runs in a little ditch dug to drain the marsh. The current of the water is rapid, on account of the great fall along the ditch. At the lower end of the marsh, large bodies of the peat have broken off, turned over, and slid- den down the declivity for several rods along the declining, underly- ing, slippery clay, resembling the action of ice blocks sliding away from the lower end of an Alpine glacier. The peat is somewhat fibrous in texture. When cut in square, brick-shaped blocks and dried, it is light and porous, but burns with a light, white-colored flame, making little smoke, and leaving a light, chocolate-colored ash. On account of its lightness, fires made from this fuel would have to be often replenished. No peat machines have yet been tried in this marsh, but there is no reason why this peat could not be manufac- tured into a valuable and pleasant fuel, by the aid of a good con- 72 ECONOMICAL GEOLOGY OF ILLINOIS. densing machine. The ease with which this bog can be drained, and its proximity to one of the depots of the Western Union railroad, afford peculiar facilities for manufacturing the fuel, and transporting it when so manufactured. In addition to being used as an article of fuel, peat might be ex- tensively employed as a fertilizer of the soil. If dug out of its native bed, slightly dried to reduce the labor of handling, and mixed with a small amount of wood ashes or quicklime, it makes a fertilizer equal to the best barn-yard compost. The mucks and poorer qualities of peat answer this purpose about as well as the finer qualities. The ashes or lime correct the natural acidity of the peat itself, and sweeten what would otherwise be too sour for an application to the soil. Lime can readily be burned from any of the neighboring quar- ries. The Wood used would not only change the kiln into the lime required, but would leave a large amount of ashes to be used for the same purposes for which the stone was burned into lime. We have much faith in the future economic uses of peat; and although we would advise due caution in the expenditure of money in experimenting with it, nevertheless we would like to see some of the Stephenson county people expend some capital in developing what we believe to be a source of material wealth. The peat experiment is not yet, perhaps, fully solved, but whoever does fully solve it will not only enrich himself, but will confer a great blessing upon the inhabitants of these northern prairie counties. CHAPTER IY. CARROLL COUNTY. Physical Geology. Carroll county is situated in the northwestern part of the State of Illinois, and is bounded north by JoDaviess, east by Stephenson, south by Ogle, Lee and Whiteside, and west by the Mississippi river. It contains an area of about 450 square miles. By surveys of the Illinois Central railroad, its elevation above Lake Michigan is about 400 feet, and above the mouth of the Ohio river at Cairo about 800 feet. About one-third of the county, the northwestern, is somewhat rough, being mineral, or "lead-bear- it g" land. The surface of this is hilly, and sparsely timbered, but in the valleys, along the streams of this part of the county, many excellent farms have been opened. The usual alluvial bottom skirts the Mississippi, being from half a mile to four miles in width. Im- mediately adjoining the river there is a belt of heavy timber; but the rest of this bottom is composed of drifted sand banks, marshy swamps, and rich tracts of the best pasture and farming lands. The southern and eastern parts of the county are composed of gently rolling prairies, with here and there an island-like grove, as if the fingers of the retiring ocean had stroked the soft surface into swell- ing undulations. The agricultural portions of the county are perfect garden spots rich in their almost virgin soil and manifold resources of wealth. Nor is the county wanting in picturesque scenery. Car- roll creek, flowing west through its center, and Plum river, running through its mineral land, have each cut channels deep into the un- derlying rocks. These are piled about in massive grandeur are crowned with evergreens ; and are, in many cases, the abodes of wonderful echoes. Above Savanna, along the Mississippi river, the huge towering Niagara rocks lift their heads like a Cyclopean wall. Geological position. We are deep down in the geologic world almost in the line of union between the upper and lower Silurian 74 ECONOMICAL 'GEOLOGY OF ILLINOIS. systems. Three distinctly marked groups of the rocks outcrop in Carroll county. These are the Galena limestone, Cincinnati group and Niagara group. Above these are the usual deposits belonging to the Quaternary system. The Galena Limestone. This is a massive, grayish, yellowish or brownish-drab colored Magnesian limestone friable and coarse- grained near its union with the clays, but very solid in its lower stratification. In. JoDaviess county it is estimated to be about 250 feet thick; in this county it has never been accurately measured, but is perhaps somewhat thinner, as we are on the edge of the lead basin. Its heaviest outcrop commences near the geographical center of the county. Thence westward heavy ledges of it outcrop along the banks of Carroll creek almost to Savanna. North of this little stream similar outcrops may be found along the banks of Plum river. The former of these streams especially, has cut its channel deep into this rock. Along this stream an anticlinal axis seems to run, as the rocks dip slightly in both directions from the creek, and a slight upheaval must have once taken place here. Along the ridge of elevation thus formed a fissure naturally would be left. The frost, the rains, and the tooth of old Father Time disintegrated, wore down and gnawed away the rocks until the fissure became partially filled. This, in process of time, formed the little valley in which Carroll creek now runs. This is the famous "lead-bearing rock" of the Northwest. The ore occurs in fissures and caverns running through the rock, in the form of what the miners call "sheet" and "cog," or crystallized mineral the common sulphuret of lead. In the reddish clay over- lying the rock, and formed by the decomposition of its upper beds, "float" ore is found; never, however, in very large quantities. Min- ing operations have never been carried on on a large scale, or on scientific principles. The "diggings" extend for several miles north and west of the town of Mt. Carroll. The pick, spade, common windlass and bucket, are the only machinery in use. Little more than a livelihood has ever been made by these primitive miners. For a long time it was thought a system of deep mining would re- veal heavy deposits of the. ore. In two instances companies were formed, and a considerable amount of capital invested. In one in- stance water compelled the abandonment of the mine, and in the other nothing was ever found to repay a tithe of the expenses of the company. This surface mining will still go on as a temporary employment for those whose other employments are not steady; but no one will CARROLL COUNTY. 75 probably be found willing to spend money enough to thoroughly test a system of deep mining. The deepest section of this rock, measured by me, is one hundred and fifty feet, but the bottom was not exposed, and extended down indefinitely. The early writers have been treating the Galena limestone as a separate system. We believe it is now coming to be regarded as a member of the Trenton limestone, none of which latter rock out- crops in this county, although it is reached in sinking deep wells in the southeastern part ; and one quarry of the real blue Trenton limestone is now worked in Ogle county, two or three miles from the county line. Of the characteristic fossils, the Receptaculites Oweni, or "sun- flower coral" of the miners, is the most usually observed, and very perfect specimens are sometimes found. Orthocera, several feet long; several species of the Orthis; corals of a number of species also abound. A very interesting species of trilobite has left its remains in these rocks ; and we firmly believe that many new fossils will be found, when the quarries in this rock are carefully and scientifically examined. Of the economic value of this rock we will speak again. It is the underlying rock in perhaps two-thirds of the county, em- bracing the central, northern and eastern parts, being our chief building stone. The Cincinnati Group. The gentle slopes from the Mississippi bottom lands up to where the bluffs are capped with the castellated crags of the Niagara rocks, if exposed, would reveal outcrops of this group. Some of the small streams have cut down into this forma- tion through the overlying Niagara. Johnson creek, winding in a sinuous course from the central to the southwestern portion of the county, shows the same rocks, sometimes near the surface. One- half of the southern part of the county has this as the immediate underlying formation. About one mile below * Savanna there is a fine outcrop, where the county road cuts the side of the hills. About one mile above Savanna there are considerable quarries opened in this formation, on the side of the bluffs. Here the forma- tion, as near as we can measure, is 80 feet thick. This is the best place in the county to make a section. At some large springs, just at the level of the Mississippi, in a full stage of water, the group begins, resting solidly on the Galena limestone as a foundation. Far up the hillside, the overlying Niagara rocks are just as dis- tinctly marked. In the railroad cut, on the Tomlinson farm, some four miles southwest of Mt. Carroll, may be found another, and perhaps the finest exposure in the county. At Bluffville, also, it is 76 ECONOMICAL GEOLOGY OF ILLINOIS. exposed by quarries. There are, however, few natural exposures of this rock. It soon disintegrates and crumbles away. Gentle hills and slopes, and graceful undulations are characteristic of its physi- cal geography. Many springs burst out from the bases of these hills, and marshes and swampy places are not unfrequent. Shales and shaly limestones compose a large part of the rocks of this group ; but its lower beds are sometimes solid and massive enough for a building stone, and even contain lead in small quantities. These shales are of a bluish-white color. Their particles are finely comminuted, as if deposited in deep, peaceful seas. A vast amount of carbon is contained in the black shales of this group. Specimens taken from near Savanna and from the Beers Tomlinson farm are almost as black as cannel coal, and burn with an oily bright flame for a considerable time. Misled by this, some capital has been expended at the latter place in boring for coal, and nothing but experience will convince those engaged that such a search is useless. One of our citizens also succeeded in extracting some oil, which he pronounced petroleum, out of similar specimens. When the great oil excitement arose in the country, an oil company was formed here, and but for the advice of the geologists, this company would now be spending its money in a vain effort to strike oil. The geologist of Iowa, Prof. WHITNEY, estimates that the carbon of these rock, if gathered into one strata, would form a bed twenty-five feet thick. Whence came this mass of combustible matter in these old Silu- rian rocks? No geologist, to my knowledge, has undertaken to answer this question. Is it of organic origin, the remains of an ancient vegetation? Is it the result of animate life, the coral? HALL'S Iowa report states that no trace of vegetation has as yet been observed in the widely distributed shales of this group, except a few traces of fucoids in the Utica slates of New York. This makes him doubt the vegetable origin of this bituminous matter. In this county, however, we have discovered fucoids woven all over the tops of some of the strata in this formation. May it not be that a con- dition of things similar to that in the Carboniferous eras existed over the broad basin in which these shales were deposited ? The vegeta- tion consisted of the lowest orders, such as would decay and leave few traces of their existence. The disorganized remains would alone remain in the form of carbon or coaly shale. The day may come when this substance, whatever it is, will be of economic value, for CARROLL COUNTY. 77 light or even fuel. With this~ brief notice, we must dismiss for the present this very interesting question. This formation is prolific of fossils. Countless remains, with an occasional perfect specimen of the splendid large trilobite, the Asaphus gigas, are the most noticeable. Orthis occidentalis and 0. testudinaria abound. Some of these shales are covered with beautifully marked dendrites. Fucoids are also found. Orthoceratites and a large Litu- ites have been found in it, together with numerous other fossils. The Niagara Limestone. This is OWEN'S "pentamerus beds" of the upper Magnesian limestone. It is next in order above the group just considered. The traveler on the Upper Mississippi must have been struck with its bold and picturesque appearance as he passed between Fulton City and Dubuque. Now the bluffs sweep down to the water's edge ; now they trend off in a semi-circular direction, as if for the site of a colossal amphitheater. Their bases indicate the gentle slopes of the Cincinnati shales, but their summits are capped with the Niagara rocks. Like vast mural structures they rise along the highest elevations, weather-worn into all kinds of fantastic shapes now displaying in their escarped cliffs resemblances to old forts and ruined cathedrals, time-worn castellated battlements, or distant spires and minarets of some old town. Such is the appear- ance of these rocks along the river bluffs above Savanna and towards the southern line of the county. The beholder, especially if he be a geologist, feels a strange spell stealing over him. Mighty visions of the old geologic ages enrapture his soul. A leaf from the old stone book is upturned before him, and he reads in the great Bible of Nature her sublime truths. He has discovered hard sense, com- mon sense in the rocks. But enough of dream and fancy sketching. Leaving the river, we do not find exposures of this limestone. Over the northern and northwestern portions of the county, all the highest portions are covered with it, in broken, fragmentary masses. Once it doubtless covered a large part of the county, but it has been denu led and carried off, leaving chert beds, corals and fragments of the rock itself as memorials of where it once existed as the surface rock. The frost, the rain and the atmosphere pulverize the Niagara rocks, and the chert beds in them being harder, settle down, like a crop of white flints sown over farm, field and hill. These chert beds show that the water of the old Niagara seas contained much silica in solution. The Niagara limestone abounds in fossils. The most common and characteristic is the beautiful Pentamerus oblongns, or "petrified 78 ECONOMICAL GEOLOGY OF ILLINOIS. hickory nuts" of the miners. But the old Niagara seas were par- ticularly the homes of the coral builders, and these minute animals swarmed in countless myriads everywhere, leaving their fossil monu- ments. Among the most characteristic are the Farosites favosa, F. Niagarensis, Stromatopora concentrica, Halysites catenulatus, and many other species and genera, containing, doubtless, new and uncle- scribed corals. This brings us through the Illinois rocks as developed in this county. Sometimes traces of the Trenton proper are found in the southern part, but they hardly deserve a place in the surface geology of Carroll county. The rocks of all three of these formations possess value as build- ing stone. The Galena ranks first, and the Cincinnati group last in economic value. THE QUATERNARY SYSTEM. Alluvium. The Mississippi bottom, from Savanna to the south line of the county, in width averaging nearly five miles, is composed of this recent river deposit. The same deposit also exists north of Savanna, on the Mississippi, and along some of the small streams in the interior. Some of it is a rich, deep, black and rather wet soil ; much of it consists of sandy deposits, while a portion forms our very best agricultural lands. The Loess or Bluff formation does not exist to a great extent in Carroll county, unless the soil and subsoil of our productive prai- ries belongs to this deposit. Some of our bluffs, as for instance where Johnson creek breaks through to the Mississippi bottom, are composed of the Loess clays. The Drift formation is also manifest in our county to a consider- able extent, although some seem to argue that it is undetected in the Galena lead basin. Deposits of Drift in our county can be found resting immediately on the Galena rocks. All our little streams almost have cut down into deposits of boulder and gravel beds. The following section, made in a well in the town of Mt. Carroll, might be taken as a fair type of the superficial deposit resting upon our rocks, beginning at the top and measuring downwards : Feet. Black prairie mold 2 Yellow, fine-grained clay 13 Common blue clay 2 Reddish clay and gravel 15 Tough blue clay 2 Coarse, stratified gravel bed 3 Pure yellow sand bed 11 Black, mucky clay 5 53 CAKKOLL COUNTY. 79 Another well, some three miles distant, passed through a second soil some fifteen feet below the surface, and immediately thereafter a deposition of timber or wood, two or three feet in thickness, many of the pieces having tenacity enough to hold together for months after exposure to the atmosphere. This well is on the farm of Felix O'Neal, and at the time of its opening was considered an object -of much interest. We cannot leave this part of our subject without again adverting to the boulders. For us they have a peculiar charm and interest. These "nigger-heads," "hard-heads," or lost rocks, abound in many places, where the streams and rains have carried the soils away. Oftentimes they are associated with gravel beds of the transported drift. Among them have been found several nuggets of copper, one of which was found lodged in a crevice of one of our Galena quar- ries. Some of these boulders are striated and furrowed by the glacier or the iceberg. Quartz, feldspar, granite, gneiss, hornblende, por- phyry, syenite, and various combinations of these and other min- erals, make up these traveled rocks. Would that we could have the true history of one of thes# lost, rocks real old cosmopolitans in a primal world. What a wonderful interest would cling around its wanderings from the time when it left its home among the Plutonic rocks of Lake Superior, until some iceberg dropped it into its present bed, through gently-moving cur- rents towards the southwest. Ocean streams rolled these uncouth stones for ages at the bottom of the "vasty deep;" frozen into glaciers, they have been pushed along their snail-like pace; adher- ing to icebergs and ice-fields and ice-floes, they floated hither and thither through Northern seas, until the ice dissolved in the genial warmth. Could we know their true history, the "masquerade of the elements," the lost history of the world, would be made plain as a well-conned lesson. The associated pieces of water-worn copper are "finger-boards" telling from whence they both came, and the direction of the ocean currents which deposited our Drift. CHAPTER Y. WINNEBAGO COUNTY. Winnebago county derives its name from a powerful tribe of Indians of that name who once roamed over its fertile prairies, which then formed a part of their hunting grounds. It is bounded on the east by Boone county, on the south by Ogle county, on the west by Stephenson county, and on the north by the State line between the States of Wisconsin and Illinois. It is twenty-four miles wide from east to west, and twenty-two and one-half miles long on an average from north to south. It therefore contains about five hundred and forty sections of land. The townships, as named, are not all bounded by township lines, but in part by streams and imaginary lines, making the townships thus different in size and shape. Its general level is perhaps somewhat higher than that of Stephenson county, although we have no information of the actual figures. The face of the county is high, dry, somewhat more sandy, rolling and undulating than Stephenson, with which we are now comparing it. A considerable portion of its surface is covered with timber of various qualities. In the northwestern part of the county, along Sugar river and its tributaries, and along portions of the north bank of the Pecatonica, there is much scattering timber and brush land, interspersed with occasional swampy tracts. A few miles below Kockford, along the north bank of Eock river and extending north and west from the same, there is a tract of barrens covered with brushwood and a rather light growth of white oak and black-jack timber. In the southeastern portion of the county, along and near the Kishwaukee creeks, the face of the county is rough, hilly, barren, brushy and covered with an occasional growth of fair timber. The rest of the county is chiefly prairie, interspersed with many beautiful but small groves. WINNEBAGO COUNTY. 81 It is well watered with many fine streams. Eock river enters it about six miles from its northeast corner, at Beloit, runs nearly due south some eighteen miles to Eockford, then bears off gradually to the west and enters Ogle county some fifteen miles south and west of the latter city. This noble and beautiful stream, and its broad, rich valley, fills the mind of the beholder with admiration. The waters of this stream are silvery and clear beyond any other river in the State; its bottom, for the most part rocky and sandy, its current swift and strong, its flow and volume constant. Heavy water powers at Beloit, Eockton and Eockford afford splendid manu- facturing facilities; and all along the stream, every few miles, dams might be constructed which would cause thousands of busy wheels to toil in the service of man. At these three places scores of founderies, factories, machine shops, manufacturing establishments, paper mills, grain mills, and other similar enterprises, attest the capabilities and power of this magnificent river. The next stream in size is the Pecatonica river. It enters the county on the west, some eight miles from its southwestern corner, and flows in a general east and north course, about twenty miles, to near the town of Eockton, where it mingles its turbid waters with the bright, flashing current of Eock river. If possible, its course is more tortuous and its waters more muddy in Winnebago than in Stephenson county. Sugar river comes in from the north- west, and enters the Pecatonica near the village of Shirland. Both these streams have bottoms of rich, deep alluvium, from one to perhaps three miles wide. Neither of them afford any water-power. Both of them, we believe, are dammed, in the water-mill sense of the term ; but such lazy rivers will never make whirling wheels hum the songs of" busy labor. The two branches of the Kishwaukee unite near the southeastern corner of the county, and flow on, a considerable stream, until their commingled waters fall into Eock river, in the township of New Milford. Killbuck creek, in the southeast ; Kent creek, coming in at Eockford ; the Kinnikinick creeks, in the neighborhood of Eoscoe ; and another considerable stream, a tributary of Sugar river, in the northwest, are the most important of the smaller streams, and with their little feeding tributaries afford plenty of water for agricultural purposes, together with a number of light water-powers. Some of the Indian names of these streams have a very descrip- tive significance. Pecatonica, as before mentioned, means "crooked stream," or "muddy waters/' and so far as the stream is descriptive G 82 ECONOMICAL GEOLOGY OF ILLINOIS. of the name, it ought to mean them both. Sinissippi, the Indian name of Rock river, signifies "the rocky river." Kishwaukee means "clear waters," a name reasonably descriptive of the streams. Win- nebago means "the fish-eaters." Taking, therefore, all things into consideration, Winnebago county is hardly so good a county for agricultural purposes as its western neighbor, Stephenson. The soil is hardly so fat ; the amount of poor land is proportionally greater. But taking into account its manufacturing interests and facilities, the unexampled fertility and Rhine-like beauty of its Rock River Valley, and the enterprise and wealth of its grove-besprinkled city of Rockford, it would puzzle a jury to decide which is the most desirable county. Geological Formations. The geology of Winnebago county is of the simplest character. First, there is the usual Quaternary deposits, consisting of sand, clays, gravels, boulders, subsoils and alluvium. After these, the three well known divisions of the Trenton limestone outcrop along the streams and hills, and show themselves in the railroad cuts, wells and quarries in different parts of the county. These are the Galena, Blue and Buff limestones of the Western geologists. A perpendicular section, as near as we can construct it, exhibits the following strata : Feet. Quaternary deposits. Average depth, about 15 Galena limestone 96 Blue limestone 35 Buff limestone 45 The measurements of the limestones are made at actual worked outcrops. At no place could we discover the St. Peters sandstone, although it must come well towards the surface about Beloit and Rockton. Neither could we discern remains of the Cincinnati group, although the thickness of the Galena would indicate that patches of it might exist. We believe, however, that the Trenton limestones are the only ones at any place exposed or dug into in the county. Surface Geology. Alluvial Deposits. The usual alluvial bottoms exist along the Rock, Pecatonica and Sugar rivers. These are from one to five miles wide. On the two latter the deposit is deep, black, fat and rich, supporting in places a heavy growth of timber, and where cul- tivated affording the usual superior Indian corn land of flat river WINNEBAGO COUNTY. 83 bottoms. The deposit along Eock river is not so rich, being com- posed more of sands and clays, with occasional patches and strips of the fatter soils. Loess Some of the bluffs along Bock river are in part composed of Loess clays, in which no fluvatile shells were noticed. This form- ation, however, is of quite limited extent. The Drift Proper. The Drift, now the subject of grave discussion among the geologists, is very largely developed in Winnebago county. It is composed of loose detrital matter, often of considerable thick- ness, brought from long distances and deposited over large areas of the county. The materials making up this loose mass were not de- rived, to any great extent, from the underlying Trenton rocks, but came from the metamorphic regions of the north. Whether brought by the currents and flow of waters, or transported adhering to the sides of those slow moving, pale-green mountains, the ice-bergs; or ground and pushed and moved along by creeping, all-powerful glaciers, we shall never perhaps positively know. All of these causes may have contributed to these results, but the appearance of the gravel beds themselves indicate the long- continued action of water. This is much more evident in the Winnebago than in the Stephen- son county gravel beds. The railroad track from Beloit to Caledo- nia, every few miles, cuts through the top of long undulating swells of land. These swells are pure, unmodified, unstratified Drift. They are made up of assorted and well rounded gravel of all sizes, from that of a pistol bullet to that of a goose egg, intermingled with a white or yellowish-white sand, and occasional small boulders, and are sometimes ten or fifteen feet in thickness. All the rail- roads exhibit the same beds along their tracks, though in a less marked degree. Every township in the county has more or less of these gravel beds, and their underlying associate deposits of clay and sand. Along some of the prairies, and in the little streams, huge boulders, the size of a haycock, are sometimes seen, partially sunk into the soil by their great weight. Two of these particularly attracted our attention. One was black ' as night, but bisected through the middle by a vein of flesh-colored granite three-fourths of an inch in thickness. We once saw one precisely like it, and evidently from the same locality, in Clark county, Missouri. The other was flame-colored and planed smooth on two sides, nearly at right-angles, evidently by glacial action. These lost or transported rocks, the story of whose journey from the north is wrapped in so deep mystery, clay and sand-banks, with faint lines of stratification in some instances, assorted gravel beds, nuggets and boulders of 84 ECONOMICAL GEOLOGY OF ILLINOIS. copper, rounded to smoothness by erosion of the waters ; all these, left in their present positions, by the fingers of the retiring seas, slightly modified, in some cases, by subsequent agencies make the study of the Drift in this county attractive, and are full of lessons of thought to the contemplative mind. A more particular description of the materials in these and simi- ar gravel beds will be reserved until our report upon Ogle county is written. The Trenton Formation. The Galena Limestone. Two-thirds of this county is underlaid by this rock. It is a heavy-bedded, yellowish, cream-colored, dolomitic limestone, compact, irregular, somewhat crystalline towards the middle and bottom strata, light-colored, porous, crumbling, and full of sand in little cavities toward the top. In some localities the bottom layers pass gradually into the blue shaly parts of the Blue division, that it is difficult to place the line of demarcation be- tween the two. An imaginary line entering the county about the southeast corner of the township of Koscoe, drawn thence in a southeast course until Eock river was reached ; thence extended round in a slight bend towards the northwest, until within a short distance of the Pecatonica river, at a point about four miles west of its mouth ; thence meandering along the Pecatonica from one to two miles south of the thread of that stream, until the western boundary line of the county was reached ; thence starting south and keeping around the boundary lifte to the place of beginning, and embracing about two-thirds of the county, would indicate the super- ficial extent of this division, to which would have to be added a narrow strip, extending from the village of Pecatonica, up towards and nearly to the northwestern corner of the county. The most notable quarries and outcrops within these boundaries were the fol- lowing. The first heavy outcrop of the Galena limestone exposed on Eock river, after it flows upon the same, is about three miles above Eockford. A high bluff on the north bank of the river pre- sents a bold escarpment, some seventy-five feet in height. At this place a large quarry is opened. The stones are hard, compact and subcrystalline, and burn into the very best quicklime. A little steamer, towing a couple of stone boats, makes daily trips in the summer season from this point to the perpetual New York lime- kiln in the city of Eockford, transporting thither the large quanti- ties of stone daily burned into lime at this greedy stone-devouring WINNEBAGO COUNTY. 85 kiln. Drifting down to the city we find the next heavy outcrops. One mile east of Eockford, along a prairie ridge, there is an expos- ure about forty feet thick, where a light- colored, whitish, friable stone is quarried to a considerable extent. In the timber ridge, about one mile north of the Fair grounds, is another, about ninety- six feet in thickness, where the workmen have penetrated entirely through the Galena limestone, and about five feet into the Blue limestone below it. The line of demarcation is strongly defined. No brick wall builded upon a stone foundation ever presented a more marked contrast. Three miles below the city, in a bluff on the west bank of the river, is a worked outcrop thirty-five feet thick. The bluffs here present a bold and picturesque front. Clambering vines festoon their face. A crown of timber sits along their brow. A narrow strip of greensward runs along their base, on which the shadows of some graceful elms delight to lie. The river, broad and many-voiced, goes careering by. There are few more refreshing spots than this, of a hot summer day, when the fierce sun is beat- ing down on cliff and terrace, dusty road, and murmuring river. Some half dozen miles below this, and not far from the Ogle county line, is an exposure in the timber, about six feet deep. Thus the valley of Eock river, for two-thirds of its extent in Win- nebago county, is hollowed out of the Galena limestone. The Galena division of the Northwestern railroad enters the county near the village of Pecatonica, on the west, and leaves it at the village of Cherry Valley, on the east line. In all its cuts and ex- cavations it shows the lead-bearing rocks. It passes nearly over the center of that part of the county colored to represent them. At Cherry Valley a heavy quarry of these cream-colored limestones has been worked, out of which the massive stone for the railroad bridge and piers at this place were taken. Out of a crevice in this quarry several nuggets of pure copper were taken, the larger of which were sold to the tinners, or found their way into eastern museums. Be- tween Eockford and Winnebago station there exist several light ex- posures, where excavations are made through the low hills. Two miles and a half below Cherry Valley, down the Kishwaukee, is a lime-kiln, where we found a man asleep, and all our hammer- ing in the quarry did not wake him. A good lime is here burned out of the Galena. A mile further down, at Trink's quarry, an exposure of fifteen or twenty feet is laid bare, and many cords of stone have been taken away. In the bottom of this quarry we found a curious genius, boring away with a horse-power drill for a deposit of copper, on the faith of some witch-hazel and some pieces of float- 86 ECONOMICAL GEOLOGY OF ILLINOIS. copper found, according to neighborhood tradition, in the quarry years ago. The Kishwaukees, before and after their confluence, cut into the Galena for the whole distance of the county, and all their hills and banks show its unworked and weather-stained outcrops. One of the heaviest outcrops in the county is a little east of the station of Harlem, on the railroad' leading from Eockford to Cale- donia. The cut passes through a rocky hill, several hundred yards in length and about eighty feet in depth, at the comb of the eleva- tion. A side-track, passes through the great ditch, on which cars are switched and left to be loaded. Derricks on either side lift the mas- sive stones, and gently lower them on the cars. The strata here are massive and solid. They furnish splendid material for heavy railroad masonry, and many hands are kept constantly employed blasting them from their adamantine foundations. We know of no quarry in Northern Illinois so valuable as this for railroad purposes and con- venience. The top of the hill is covered with a fine, limey, white clay. Gravel and boulders also abound in the neighborhood. About Winnebago, Argyle and along south of Harrison, are many light quarries worked into the Galena. In fact, without further particular- izing, all that part of the county bounded by our imaginary line circumscribing the Galena, is underlaid, at no great depth, by this famous lead-bearing rock. The only fossil found in abundance, is the characteristic Recepta- culites Oweni. The quarrymen and miners speak of it as the "honey- comb," "sunflower coral," or "lead fossil." About Eockford speci- mens are exceedingly numerous, but generally break to pieces before finding their way into the cabinet, on account of the friable nature of the upper strata, in which they are mostly found. Judge Miller has a specimen almost as round as an apple. This specimen, when we were in Eockford, was borrowed by an enthusiastic geologist, and we did not see it. But few other fossils were found. The Blue Limestone. The Blue limestone, or Trenton proper of the older Western geologists, next succeeds the Galena in the de- scending order. It is largely developed in the northern and north- western part of the county. It is here a thin-bedded, bluish-gray limestone, calcareous, or with a lime base, but some of the shaly partings have a clayey base. In the bottom of the deeper quarries a very blue strata always exists. This is massive, and conchoidal or glassy in fracture, and in the mining region is known as the "glass rock." A line drawn from a point in the western boundary line of the county, some two or three miles north of where the Pecatonica river enters it, along the north edge of the alluvial bot- WIXNEBAGO COUNTY. 87 torn of this stream to a locality about midway between Shirland and Eockton; thence east of north to the northern boundary line of the county; thence west round the county line to the place of begin- ning, would bound the superficial area underlaid by this deposit, except that the extreme western part occasionally shows beds of passage into the overlying Galena, and except that a considerable patch of the Blue rocks exist in the extreme northeastern part of the county. The first and second railroad cuts, east of Shirland, made by the Western Union railroad in excavating for their track, afford the best exposures examined for investigating the Blue limestones of the Trenton series. The first is about eight hundred feet long and thirty feet deep ; the second is about four hundred and fifty feet long and fifteen feet deep. The rocks are of a whitish-gray color, with con- choidal fracture* becoming darker colored as the lower strata of the quarries are reached. Further west, about Durant, the stone shows a nearer approximation, in lithological characters, to the Galena. The elevations here are capped with the latter rock. The Sugar river hills are rock-ribbed with the division of the Trenton now under consideration. The fossils noticed in the railroad cuts near Shirland were so numerous as to' make their description at this time too tedious. They were mostly small and fragmentary. Some of the thinner and more shaly strata are covered with shells, fragments of trilobites, stems of the encrinites, and pieces of corals, so thick as to resemble masses of fossils stuck together by some adhesive paste. The same lime- stones at Dixon are exactly similar in appearance. The Buff Limestone. This is an unevenly-bedded, somewhat argil- laceous or clayey dolomite. It is, for the most part, of a light- yellowish or brownish color, shading into blue towards the bottom of the quarries ; is not very homogeneous in composition or stratifi- cation, presenting in some of its layers an earthy and in some a crystalline appearance. In every outcrop, worked to any consider- able extent, the lower layers become quite massive, and of a dark- blue color. When first taken out, this blue stone presents a beau- tiful appearance, and no materials make handsomer mason work; but when exposed to the weather for some length of time, the dark, rich, blue color fades into a dirty, whitish-blue, not so beautiful as the original color. This rock, however, makes a good building stone, but, on account of its earthy base, does not burn into a good lime. But a limited portion of the county is underlaid by this formation. If from two points in the boundary line between Wisconsin and Illi- 88 ECONOMICAL GEOLOGY OF ILLINOIS. nois, distant from Eock river on each side three or four miles, we extend two lines southward, following the general course of the river, but drawing gradually nearer together until a point in the center thread of the stream was reached one or two miles south of the north line of Harlem township, the tongue of land thus inclosed would represent this portion. The chief outcrops of the formation, and in fact the only ones where it can be satisfactorily examined, are at Beloit, a short distance within the State of Wisconsin, and at Rock- ton, about the middle of our tongue-shaped strip of land. The quarry at this latter place is opened on the north face of a low range of hills, ranging along the south bank of Rock river, and dis- tant one mile from the village. The outcrop, as here worked, is forty-five feet thick, and answers well to the above description, ex- cept that the upper ten or fifteen feet resemble beds of passage into the overlying division. This outcrop, together with its closely resem- bling ones at Beloit, in Wisconsin, and at Winslow, in Stephenson county, and at Martin's Mill, in Wisconsin, exhibits about the follow- ing section : Feet. 1. Light-colored, chocolate-brown clay, covered with a thin soil, full of large, unworn gravel, not apparently transported, but the undecomposed "parts of shaly strata or layers formerly decayed or rotted into clays about S 2. Thin-bedded, bluish-yellowish strata or layers, breaking with a mqre or less glassy fracture, and in some cases having a vitreous appearance, and in all cases re- sembling corresponding layers in the overlying limestone 15 3. A layer resembling the last, but heavier-bedded and duller colors 6 4. One, and sometimes two, layers, separated b,y clayey shales and loose clays, of heavy-bedded, massive, very blue limestone, with less conchoidal fracture than corresponding layer in Blue limestone 4 5. Heavy-bedded, massive, dull sand-colored limestone, very impure, breaks into irregular masses, and to the tongue has both a sandy and clayey taste 7 6. Clays, and clayey and sandy shales 3 The upper part of all these outcrops, in our judgment, differs in but a slight degree from quarries in the Blue limestone of the same thickness. The lower part of the quarries, for four or five feet above and below the blue strata, has a more marked difference. But inas- much as Professor WHITNEY, and other eminent geologists, class these quarries as the Buff limestone, and inasmuch as the types of char- acteristic fossils are somewhat different, we shall describe and map them in these reports as belonging to this division of the Trenton formation. Fossils. The characteristic fossils of the Buff limestone, observed at Rockton, consist of fragments and indistinct traces of fucoids : Cephalopoda, of the genus Orthoceras, Cyrtoceras and Lituites; Gastero- poda, of the genera Pleurotomaria and Murchisonia; Brachiopoda, of the genera Orthis and Strophomena,- Lamellibranchiata, of the genera, Tellinomya and Ambonychla; and zoophytes or corals in fragments. WINNEBAGO COUNTY. 89 The Pleurotomaria subconica, Oncoceras pandion, Tellinomya cuneata, Ormoceras tenuifilum, Tellinomya ventricosa, and species of Orthocera and Ambonychia, are the fossils occurring in the greatest, abundance. The casts of some of these come out in great perfection. Economical Geology. Building Stone. All three of the above described formations or , divisions of the Trenton rocks furnish stone adapted for building and ordinary mason work. Especially is this true of the Galena limestone. The quarries at Harlem and Cherry Valley furnish excel- lent materials for solid and massive railroad masonry. The public school building in the city of Bockford is a model of architectural beauty and solid imposing grandeur. No painter's art could improve its present rich, warm color. The beautiful cream-colored residences scattered about the city present an equally striking appearance. When dressed and laid up of equal thickness, nothing can excel the effect of these stone residences. We have heard much said of the beauty and aristocratic appearance of brown-stone fronts in other wealthy cities ; but no stone ever quarried, unless it be the marbles or the flesh-colored granites, present a more striking, solid, home- like appearance than these same cream- colored limestones of the Forest City. When built up as these people know how to build them, they are an architectural miracle of stone and mortar. The rich, warm, soft, cream-color attains its richest, warmest and softest hues in the stones taken from the Eockford quarries. It bathes them with a tint beautiful as Nature uses, when, with a brush of sunbeams, she lays her golden-yellow upon the ripe ears of corn. And not only is the material beautiful, but it is lasting, seasoning, when long ex- posed, into almost the hardness of granite itself. Let wealthy builders hereafter, instead of sending for Milwaukee brick to put into their palatial residences, go to the rich outcrops of the Galena limestone, and dig from thence a building material every way more durable, more beautiful, and more simply grand. The Buff and the Blue also furnish stone of good quality for all ordinary mason work, and it is easily quarried and easily worked. The dark blue strata, when handsomely dressed and laid up, either by itself or alternating with the lighter-colored, presents a pictur- esque and quaint appearance : but the colors are not fixed and fast like that of the Galena. Lime. The Buff limestone of Eockton will not burn a good quick- lime, but would doubtless, if properly managed, make a fair hydraulic 90 ECONOMICAL GEOLOGY OF ILLINOIS. lime. Some of the Blue limestones will make a fair quicklime ; but the Galena limestone excels all others in the quality of this useful material, which can be obtained in inexhaustible quantities from its convenient quarries. The New York perpetual patent limekiln in the city of Eockford, before referred to, turns out thousands of bushels, every summer month, of an excellent building and whitewashing lime. It is a high structure, perhaps ten feet in diameter within its circular walls. Perpetual fires burn away at the bottom ; the sinking, glowing mass is constantly replenished at the top with cart-loads of stones the size of a man's fist; and daily from the lime-pot below, the hot, dusty, crumbly stones, soon to be transformed by the hissing touch of water into white floury lime, are shoveled into a convenient storehouse. Sands and Clays. Sands for all economical purposes are found almost anywhere along the river banks, or may be dug from thickly strewn Drift deposits. Clay, to burn into a good common red brick, may be had in almost 'any of the underlying subsoils. The subsoil clays just above the soldiers' old camping grounds, a mile or two above Rockford, are of excellent quality for brick-making purposes. While there last summer, a powerful compressing machine, called "The Little Giant," we believe, operated by a steam engine, was at work pressing dry dust into bricks solid* enough to be handled. These, when burned, came out a beautiful cherry color, rivaling in appearance and richness of coloring the far-famed Philadelphia cherry-colored brick. If the experiment then being tried proves a success, another branch of manufacturing industry will be added to the many already possessed by this energetic little city. Mineral wealth. Of this the county possesses very little. Although covered to so large an extent by the real lead-bearing rocks, no bodies of mineral have ever been found in the county. Traces of lead are found in many of the worked exposures, and bits of float mineral are often picked up in the gravel-beds ; but these are sim- ply matters of curiosity, and denote no workable bodies of the lead ore. The modes of occurrence of the galena or lead ore over the lead-basin are very peculiar. A few well-known centres of deposit exist. A radius of a few miles around these seems to be productive. All outside, even where the conditions would seem to be favorable, is unproductive. Bog iron ore exists about many of the springs, but for economical purposes the deposit is worthless. Copper, in its pure state, is often met with. No deposit of the metal exists. It is all float material, found in connection with the drift, and comes originally from the WINNEBAGO COUNTY. 91 Lake Superior copper deposits. A crevice in the Galena rocks at Cherry Valley had a considerable quantity of float copper deposited in it. It has all been removed. A railroad laborer found, in a gravel bed in the southeastern part of the county, a boulder or nug- get weighing fourteen pounds. He sold it to a tinner, who shipped it to Chicago, and it found its way into the general copper trade. Hon. Anson S. Miller, of Eockford, has in his cabinet of minerals a handsome specimen of several pounds weight, found in digging a well some thirty feet below the surface. But all these are rather matters of interesting speculation, and are not of much economical value to the county. Peat. No peat beds of value were noticed in the examinations of this county. The land is too well drained to afford favorable con- ditions for the growth of this useful material. In the region of Sugar river, in the sloughs, swales and marshes there existing to a limited extent, and about the rise of some of the small streams south of Bock river, some small beds of imperfect peat and black muck doubtless do exist; but they will never be of value as a fuel, and are only adapted for use as a fertilizer of the soil. Fruit. Apples and pears of the hardy varieties succeed well, and more than enough for home consumption is raised. The garden fruits produce large crops. The somewhat sandy nature of the soil is well adapted to the strawberry. We saw, when there, patches of ground blushing red with this delicious fruit. The crop of leaves was not heavy, but the berries lay thick in tempting bunches over the ground. Boys and women, with red-stained hands, were gathering them into baskets for the Rockford market. Orchards planted in unexposed situations, or properly protected by timber belts, bear well, and the crop is remunerative and reasonably sure. Hardy vines, with winter protection, bear bountifully, and may be made a source of profit. The strawberry, currant and gooseberry may be raised in great abundance without protection. The strawberry, how- ever, does better with a covering of coarse straw during the winter, which need not be removed in the spring. As to the grape growing and wine producing facilities of this part of the State, we refer those desirous of further information to our report upon Whiteside county, where this subject has received more attention from the horticulturists. 92 ECONOMICAL GEOLOGY OF ILLINOIS. Indian Antiquities. The Indian race is fast fading away before the resistless march of Anglo-Saxon civilization. At his present rapid decrease, the Indian will soon be a historic man. But he has left memorials which will last when the proudest builded monuments of his all-conquering foes have crumbled into oblivion. The geography and significance of our Indian names is a very wonderful subject. Flint arrow-points and spear-heads are frequently picked up, while stone axes, and smooth oblong instruments, sharp at one end, and used for skinning animals, are of not unfrequent occurrence. But the most common objects of interest to the antiquarian are the mounds, in common speech, thought to be of Indian origin. The mound-builders, whoever they were, once swarmed in the valleys and woodlands, sat down upon every picturesque spot along the streams, and left their mound-builded structures as memorial monu- ments of their busy lives. We shall not, in this place, discuss their age or their origin, but simply describe some of the most prominent ones noticed in this county. They do not belong to its geology, but they are matters of great interest to thoughtful men.. The antiquarian and archaeologist, if not geologists, are laboring in a field close bordering upon the domain of that earth-delving science. Three classes of these mounds were noticed and examined. There was the common round mound, from ten to fifteen feet in diame- ter, and from two and a half to five feet high. Mounds of this de- scription are very numerous. There is a large group of them on the banks of Eock river, six or seven miles below Kockford. At many other places along this stream they exist in scattered groups. On the north bank of the river, within the city limits of Rockford, and a short distance above the bridge on Main street, several very large ones are preserved in the private grounds of citizens. But the local- ity where they are met with in the greatest numbers is on the banks of the Kishwaukee, in the southeastern part of the county, near the confluence of the two streams of that name. Scores of them are scattered about here, and scores more have been nearly obliterated by the sacrilegious ploughshare of the white man. The oldest inhab- itants recall many occasions where bands of Indians, pilgrim-like, returned to these silent mounds, and held over them for days their mystic pow-wows. The oblong-shaped mound is of much rarer occurrence. At the locality in Rockford already alluded to there is a very remarkable WINNEBAGO COUNTY. 93 one. It is one hundred and thirty feet long, about twelve feet wide at the base, and three or four feet high. Near by this one is a mound of the third class, or those having a fanciful resemblance to some form of animal life. In Eockford it is known as the "Turtle mound." But it resembles an alligator with its head cut off more than it does a turtle. We give its dimen- sions : Whole length, one hundred and fifty feet ; width, opposite fore-legs, fifty feet ; width, opposite hind-legs, thirty-nine feet ; length of tail, from a point opposite hind-legs to end of tail, one hundred and two feet ; length, from a point opposite hind to a point opposite fore-legs, thirty-three feet ; distance from opposite fore-legs to where neck should begin, fifteen feet. These measurements were not made with exactness, but are simply paced-off guesses. The figure lies up and down the river, on a line almost north and south, the tail extending northward. The body rises into a mound as high as a standing man. The feet and tail gradually extend into a greensward, growing less distinct and unde- finable, until they cannot be distinguished from the surrounding sod. The measurements across the body at the legs include those appendages, which are only a few feet long. The effigy, whether of alligator, lizard or turtle, seems to be head- less, and no depression in the surrounding soil would indicate that the materials out of which it is constructed were obtained in its immediate vicinity. It is a curious structure, and one would like to know its true his- tory as he looks upon its partially defaced form. What were its uses, and who builded its uncouth animal proportions, may be better an- swered by the researches of the antiquarian than by the speculations of the geologist. CHAPTEE VI. BOONE COUNTY. This is, perhaps, (lie smallest county in the State, comprising only eight townships of land. It is twenty-four miles long from north to south, and twelve miles wide from east to west, and consequently contains only two hundred and eighty-eight square mile. It is sit- uated in the north tier of counties of the State, a little east of the center of the same. Its boundaries are as follows : on the east McHenry county, on the south DeKalb county, on the west Win- nebago county, and on the north, the State of Wisconsin. Its physical geography is not remarkable, and the general face of its surface not dissimilar to that of surrounding counties. The townships of Spring and Flora, and in fact all that part of the county south of the Kishwaukee, may be called a treeless prai- rie, characterized by long, low, undulating rolls, and low ranges of hills and ridges. In some places it is flat, with swales and sloughs of unlimited extent, between moist marshes and black, fat meadow lands. A few trees skirt along Coon creek in the southwest, and scattered patches of timber in one or two other places relieve the level landscape. A broad, rich, comparatively level Illinois prairie, these hundred noble sections preserve yet some of that primitive beauty, which gave two townships their names. Before the busy teeming millions of the sons of toil swarmed over the fertile West, prairie flowers, in spring-like beauty and autumnal glory, bloomed, where now the glancing plow-share turns the spring furrow, and the golden-ripened wheat fields dally with the fugitive winds. The pur- ple and golden clouds of flowers, that used to lay on these prairies, are now no more ; but in their place the tasselled Indian corn waves its head, and men are growing rich from the cultivation in useful crops of these old flower-beds of nature. BOONE COUNTY. 95 But leaving these prairies, the county changes its appearance north of the Kishwaukee. It becomes rougher and more rolling. Although still good for agricultural purposes, the soil becomes thin- ner and lighter-colored. More streams are met with. These are margined with hills to some extent, and hilly barrens. Wide stretches of rather light timber and brushwood extend for miles along the streams and over the intervening highlands. Here and there a grove of better timber may be seen. Small prairies, prairie openings, and long stretches of prairie still exist in every direction, but it soon becomes difficult to tell whether the rather poor timber or the irreg- ular prairie land predominates, especially after passing nearly into the northern third of the county. The same general remarks apply to this third of the county, except that considerable wet and swampy land is noticed. Many of the streams of the county take their origin in these low lands. The northwestern part of the county has considerable prairie, and much wet land; the northeastern has more timber, is higher and dryer, and on towards the "Big Foot" prairie, in Wisconsin, contains good farming, lands. The timber consists mostly of black, white, burr, red, yellow, and some rare varieties of the oak, black walnut and butternut, shell- bark and common hickory, cottonwood, sugar-maple, honey-locust, sycamore, water and slippery elm, haw, dogwood, common poplar, white and red ash, red cedar, white pine, linden or basswood, com- mon swamp willow, and a few other shrubs and plants. Many of these are seldom met with, and indeed the groves in this part of the country are made up principally of the common black and white oaks to be met with in the poorer timbered regions of Northern Illinois. The alluvial lands skirting the larger streams are the only places where many of the above species of trees can be noticed at all. Boone county, for the most part, is well watered. The Kishwau- kee, here called a river, enters it on the east, not far from the cen- ter of the eastern line of the township of Bonus, and crosses in long, easy flowing curves, entering Winnebago at the village of Cherry Valley. It is a stream of considerable size, not very swift current, reasonably clear waters; and affords fair water powers at Cherry Valley and Belvidere. Coon creek comes in from the south- east, and falls into it near the center of the township of Bonus. This is the only tributary worth naming on the south side, within the county limits. On the north, the Piscasaw creek comes in almost exactly on the center of the eastern boundary line of the town- 96 ECONOMICAL GEOLOGY OF ILLINOIS. ship of Boone, and flows in a southwest direction until it is lost in the Kishwaukee at Belvidere. It is a light stream too light for available water powers. Beaver creek comes in at the northeastern corner of the county, flows in a direction west of south, and joins the Kishwaukee a short distance above the town of Cherry Valley. It is similar to the Piscasaw, and not valuable for water powers. Some small streams in the township of Manchester, in the northwest part of the county, flow over towards Eock river, but they are small and insignificant. These water-courses and their small tributaries abun- dantly water the county, and adapt it to stock-raising and agricul- tural purposes. Geological Formations. The Cincinnati group and the upper division of the Trenton lime- stones are the only rocks which outcrop, or in any manner show themselves, in this county. About its northwestern corner, extending to even some distance within its borders, the middle and lower Tren- ton limestones doubtless are the underlying rocks ; but they no- where outcrop that I could notice. The deposits of the Quaternary system are extensive in the county, covering it over in many places to a great depth. It will thus be seen that the geological formations of Boone county are few, and its geology comparatively simple. The following section of the rocks exposed and the superficial deposits, is comparatively correct ; although nothing but an approximation to the thickness of the latter can be given : Section of Formations in Boone County. Feet. Alluvium, principally partially stratified clays, sands and fine gravels, along the Kish- waukee with loams and surf ace soils 20 Light-colored, velvety, tough, tenaceous, impervious potters' clay 30 Ordinary drift deposits, consisting of the usual sands, gravels, hard-pan and clays.. 35 Cincinnati shales; the formation much deeper, but worked to a depth of 18 The Galena limestone, worked 35 Lower Trenton limestones Unknown Surface Geology. The surface geology consists of the usual Quaternary deposits, except that the Loess is perhaps entirely wanting. The Alluvial deposits along the small streams are narrow, rich and black. On the Kishwaukee they are wider and deeper, intermingled with sands and fine gravels, and bear, in places, a heavy growth of bottom timber. The usual thin prairie soil, swamp mucks and peats of various degrees of purity and ripeness, make up the rest. BOONE COUNTY. 97 The Drift proper is a heavy body of abraded and transported materi- als. Over that part of the county underlaid by the Cincinnati shales there is a thinner superficial deposit of a fine, laminated, comminuted clay, of a light ashy or blue color ; bearing mingled evidence of depo- sition in still waters and the dissolving in situ of the underlying clayey shale rocks. No extensive gravel beds exist; but occasional large boulders may be noticed, more -especially lying about the low springy places. But leaving the gently rolling prairies, and going northward to the region underlaid by the Galena limestone, the reddish clays, hard-pan and coarse gravel beds of the upper members of the Drift largely predominate. A few miles west of Capron are localities where boulders, of the average size of a man's head, lay thickly strewn over the ground. These were noticed to lie thickest where boggy and springy places were met with, surrounded by rougher and more rolling land. The boulders are all from the metamorphic regions of the north, and consist of granite, gneiss, hornblende, trap, and some other varieties, with their various combinations. Across the whole northern part of the county these boulders were noticed in a greater or less abundance, associated with clays and sometimes clayey sands. Across the central part of the county the coarse gravel beds, unstratified hard-pan, and partially stratified clays make up the surface covering of the rocks. Under these, all over this region, laminated clays rest upon the indurated rocks below. Some of the gravel beds northwest of Caledonia are almost a mile long, and several feet deep. They are made up of materials very much rounded and abraided ; are partially stratified ; the gravel is of all sizes, intermingled with clean sand. A low drift hill of gravelly clay lies close to Belvidere, on which the Court House stands. In the banks of the Kishwaukee, a short distance below the bridge between the north and south parts of the city, on the north side of the stream, are outcrops of the bank of tenacious potters' clay, before referred to. It runs under at least a part of the city, and in one place borings for some public work showed it to be some seventy feet in thickness. At another locality some workmen were sinking a well. After going through this deposit, which there was much thinner, water rushed into the well so fast that the men could hardly get out in safety. In many places I heard of the traditional nuggets of copper that previously had been found among the gravel and boulders, but I 7 98 ECONOMICAL GEOLOGY OF ILLINOIS. could not succeed in finding any myself. Over this whole region, in connection with my observations upon the Drift, I watched closely in order that I might detect indications of glacial action; but I am forced somewhat reluctantly to admit that atmospheric and chemi- cal agencies and aqueous forces probably explain most of the phe- nomena connected with these superficial deposits. In the morraine- like hillocks of Ogle county glacial action, I think, is more manifest. The Cincinnati Shales. As already intimated, the shaly rocks of this deposit underlie nearly all that part of the county south of the Kishwaukee. Coon creek doubtless cuts down to Galena; but all the prairie ridges show the outcroppings of the former rocks, although worked exposures are rare. In fact there are but two good stone quarries in Boone county: one in the Cincinnati shales, five or six miles south of Belvidere, and one in the Galena limestone three or four miles northwest of the city. The former of these is opened in the brow of a low hill. A few feet of clay and subsoil is stripped from the surface of the shingly rocks. The formation is quarried into about eighteen feet in depth, and great quantities of stone have been removed and hauled for many miles over the surround- ing country, and into the city of Belvidere. The quarry, or rather series of quarries, is a source of profit, not so much on account of the valuable properties of the stone, as on account of the ease with which they can be quarried and the scarceness of all kinds of stone iu the county. We noticed here flagging stones twelve by twenty- one feet, and three or four inches thick, without an apparent crack. On some parts of the rocky walls here exposed to the air, the "tooth of time" has made a marked impression. The rock is crumbling and decaying rapidly. Draw the finger over it and a shower of small fragments fall to the rocky floor. About Garden Prairie, near the line between this and McHenry county, this formation is quarried and hauled north and northwest over the county for seven or eight miles, for purposes of ordinary stone masonry. At no other place in the county is it worked. No natural out- crops exist, on account of the ease with which it disintegrates and covers up its natural outcrops ; but it is not difficult to trace its boundaries by the gently undulating elevations, the marshy springs along their base, the color of the waters that trickle down the slopes, and the nature of the overlying clays themselves. The formation here is unfossiliferous to a high degree. Nothing but a few indistinct tracings of fucoids or sea-weeds were noticed. BOONE COUNTY. 99 The Galena Limestone. Two-thirds of this county perhaps is underlaid by the lead-bearing rocks of the Trenton limestone. And yet in all this extent of superficial area there is but one good out- ci'op, and one place where the Galena is worked to any extent or advantage. This is at the exposure on Beaver creek, about three and a half miles northwest of Belvidere. Here the quarry is worked to the depth of thirty-five feet. The stone is massive and solid. Some of the bottom layers are from six to eight feet in thickness. Much stone has been quarried here for the construction of the rail- road bridge at Belvidere and for building purposes in the surround- ing country. The country round the quarry is barrens and oak openings, with brushwood and a thin whitish soil. The upper strata of this out- crop are thin enough to be readily removed with pick and wedge and crowbar; but the lower ones can only be displaced by patient blasting. I found here many of the characteristic fossils, such as Recep- taculites Oweni, Marchisonia gracilis, M. gigas, Pleurotomaria angu- lata, Ambonychia, Bellerophon, and fragments of Orthocera. Leaving this quarry my examinations indicate that both Beaver creek and the Piscasaw, for their whole length in this county, are underlaid by the Galena limestone. From Belvidere, on a line east of north, through the townships of Bonus, Boone and Leroy, to Capron, and on nearly to the State line ; thence west a few miles ; thence south along the center township line of the county, through Shermanville, to the starting point ; thence northwest to Caledonia, and a few miles north of the same ; thence back on any convenient road to the starting point ; thence west on the north B^ckford road to the county line, and on all this extent of country gone over, I only saw indications of this limestone. Only a few imperfect, crumbly outcrops were seen in the faces of some of the little hills ; not such as would pay to work. On the Upper Beaver and round the feeding springs of one of the Kinnikinniks, some poor specimens of stone are quarried, such as are used .for the foundations of houses about Capron and in that part of the county. Blue Limestone. On the map I have marked the northwestern part of Boone county with the colors indicating the lower divisions of the Trenton formation. Its close proximity to Boscoe and Beloit, with some surface indications, led me to believe that these would 100 ECONOMICAL GEOLOGY OF ILLINOIS. be the surface rocks, if the superincumbent clays were removed. No outcrops, however, were noticed, and the matter is of little gen- eral or economical interest. Economical Geology. Building Stone. Building stones are scarce in Boone county. They are worth about five dollars per cord in the quarries, after being dug and prepared for loading. The quarry on Beaver creek furnishes a solid, massive, hard stone, very suitable for bridge piers, culverts, and other railroad masonry, or any solid enduring masonic work. It requires, however, a good deal of labor to adapt it to the lighter kinds of masonry. The stone is in active demand, owing to the scarcity of other quar- ries in the surrounding country. Most of the heavy building stones used in Belvidere, such as church foundations and other like work, are obtained at this place. The quarry in the Cincinnati shales south of Belvidere, already referred to, furnishes most of the stone used in that city for the lighter kinds of work, such as foundations for ordinary houses, or- dinary cellar walls, walling wells, and light kinds of masonry gen- erally. It also furnishes stone for a large extent of country over the surrounding prairies. The ease with which they can be quarried and broken into blocks of any required superficial area, makes them well adapted for these purposes. The layers are from two to four or five inches thick, and break with ease in any required direction. In many places the Cincinnati shales are useless as a building stone, owing to the ease with which they disintegrate and crumble away. But here they seem to answer a fair purpose for the uses to which they are devoted. At Gen. Hurlbut's residence, in Belvi- dere, we were shown some of them which had been in use twenty years, and yet they seemed little gnawed into by the iooth of time. For flagging-stones they can be obtained of any desired size and shape, and when so used in Belvidere they seem to be answering quite well for this purpose. We would not advise the use of stone from the Cincinnati group for solid work, or in structures which are to stand the test of ages. Some of it will seasdn so far as to become enduring ; but occasion- ally stones will be found, in the most carefully constructed work that can be built, which, after a few years' exposure to the rains and frosts, will begin to crumble and melt into their kindred clay. BOONE COUNTY. 101 Lime. At the Galena quarry, above referred to, a lime-kiln is in successful operation, and a good quality of common quicklime is burned. We believe, however, the city of Belvidere finds it more economical to use lime shipped on the railroad from other places. A good perpetual lime-kiln at the Beaver creek quarry would furnish abundance of good lime, and would pay well. Minerals, No mineral wealth exists in the county. Bog iron ore in some of the bogs and marshes west of Capron was noticed in considerable abundance. Pieces of float copper are frequently picked up in the gravels of the drift. Traces of lead are sometimes found in the Galena limestone. Springs of chalybeate water exist in places. But all these are matters of curiosity and interest, rather than sources of economical value. Sands and Clays. From the ordinary clay and sand banks almost everywhere abounding in more or less purity, sand for building pur- poses, and clay for ordinary red "brick, may be obtained in great abundance. The subsoil over most of the Galena rocks makes a good common brick. The bed of potters' clay, before alluded to, deserves more than a passing notice. When ground and mixed with sand, it makes a hard, handsome, cream-colored brick, quite as beautiful, and perhaps more enduring, than the far-famed Milwaukee brick. The front of the large new church in Belvidere is built of this material. For this purpose alone this bed of clay is valuable. And there is no reason why an article of common crockery might not be manufac- tured out of it in unlimited quantities. Even a queensware of fair quality might be made from this deposit. When first dug the clay is tough and tenacious. The spade is forced into it with difficulty. The color is between a milk-white and chocolate-brown. When dry it breaks with a somewhat conchoidal fracture ; has a fat, unctious feel to the fingers, and becomes lighter in color. We do not know its chemical composition. Peat. In the township of Bonus, near the residence of a Mr. Chapman, and partly owned by him, is a peat bog of about twenty acres in extent. A Mr. Brown and Mr. Dana also own peat land in the same slough. Perhaps the bog contains in all forty acres. It is in a swale or slough running down into the Piscasaw creek in an east and west direction. It is susceptible of easy drainage. I spent some time in examining this peat bed. It was covered with a dense growth of sedgy grass ; quaked and shook as we walked over it ; had the usual carpet of the sphagnum mosses spread over its moist floor, and permitted us almost anywhere readily to force a 102 ECONOMICAL GEOLOGY OF ILLINOIS. common pole down seven or eight feet. The deposit is undoubtedly nine or ten feet thick at many places. The quality of the peat is a little fibrous. It 'is grass peat rather than moss peat, although grass and moss both enter into its composition. The bed is in a splendid formation stage ; the peat is unripe peat. It might be successfully used as a fertilizer ; but in the present stage of the peat experiment would hardly make a successful fuel. When properly prepared and condensed it will make a good fuel, and it will only be a few years, we hope, when peat machines will be brought to such perfection that this, and all equally good peat deposits, will become sources of material wealth and blessings to whole communities. In the township of Manchester I also heard of the existence of peat of good quality, but did not succeed in finding the bed. Doubt- less about the little feeding streams of the Kinnikinnicks many beds of value exist, and will be brought to light when peat becomes of greater economical value. Indian Antiquities. The Kishwaukee was a favorite stream with the aboriginal inhabit- ants of this part of the country. No very conspicuous mounds were noticed, but the usual arrow-points and stone implements are often picked up. Within a few feet of the northwest corner of the court house in Belvidere the spot is yet pointed out where "Big Thunder," a renowned Potawattamie chief, was buried. His grave was surrounded with ash palisades, the bottom of which may yet be traced in the ground. He was buried in a sitting posture overlooking the beauti- ful plain to the west. He had prophesied that a final great battle would take place between his people and their pale-faced enemies, in which the latter would be perfectly defeated; and he caused himself to be buried thus that he might view the bloody conflict, and with his voice of thunder cheer on his fierce warriors, as in life he was wont to cheer them. The first settlers speak of seeing his huge skeleton sitting in its place of sepulture, waiting in vain for the great battle. By-and-by his skull disappeared, and its disappear- ance became associated in the public mind with the visit of the wandering phrenologist. But the rolling years passed on. Bone by bone was spirited away. The palisades themselves mouldered into dust. The voice of the chief and prophet was forever stilled in death. The great Indian battle remains unfought. The seat of the Indian tribe is covered with a busy little city, and the plain is alive with the pale-faced race, and full of the roar of their industry. BOONE COUNTY. 103 Agriculture and Fruit Growing. I would speak of the fruit-growing and agricultural capabilities of this county, but the remarks made in the geology of Winnebago county, upon these topics, apply to Boone county nearly as well as they do to that county, and we refer the reader to that report for remarks upon these subjects. CHAPTER VII. OGLE COUNTY. This large and excellent county is bounded on the north by parts- of Stephenson and Winnebago counties, on the east by DeKalb county, on the south by Lee county, and on the west by Carroll county, and a small portion of Whiteside county, just touching it on the southwest corner. It is thirty-nine miles from east to west, and about twenty-one miles from north to south, containing eighteen full townships of land, and about seven half- townships. It, there- fore, contains about seven hundred and seventy-three sections, or square miles. Eock river, here a broad-flowing, swift, bubble-dancing stream, flows in a diagonal direction across the county, entering it about twelve miles from its northeast corner, and making its exit about eight miles east of its southeast corner. For most of this distance the stream sweeps along in long, undulating curves, except at Grand DeTour, where it doubles upon itself in short, abrupt crooks. The river valley here is unlike itself- further north and south. The face of the county along the river is abrupt, rough, broken and timbered. In only a few places do the prairie vistas open down to the water's edge, affording glimpses of the broad undulating plains, which open so wide beyond, that the blue of the sky and the green of the roll- ing sward seem to mingle in a far-off blending. The little streams on either side have cut down through the hill, leaving bold outcrops of Trenton limestone and St. Peters sandstone. To one familiar with the sublimity and grandeur of mountain scenery as displayed in Alpine regions, or among the canons and wonders of our own Sierra Nevada or Eocky Mountain chains, where the slow-moving glacier creeps among eternal rocks down to the evergreen forests and the smiling valleys ; where the mountain-born OGLE COUNTY. 105 torrent leaps in foam along its rocky channel; where gorge and precipice and adamantine rocks, in wild confusion piled, fill the soul with awe to one, I say, familiar with such scenes as these, the scenery along Eock river, in Ogle county, may seem tame ; but to the inhabitant of the prairies, accustomed only to the grassy plains and green slopes of his native State, bedecked though they be in their native wildness with flowers of gayest hue, to him there is a charm in such scenery as a ride along the river bank from Byron to Dixon discloses. The resemblance to the old feudal castles of England, as, half- ruined, moss-covered and ivy-draped, they are preserved to us in picture galleries, is constant and recurring. The limestone bluffs, covered half way up their steep sides with the accumulated talus of ages, look like mural escarpments and Cyclopean walls among the" wild hills. The sandstone cliffs of various hues, now glancing like snow hills in the sunshine, or glowing like hills of flame or yellow, when stained with the red oxide of iron, are weathered into all sorts of fantastic shapes. The rounded, tower-like, casemated masses, which stand out in bold relief at the Indian Pulpit, three or four miles below Oregon, and at other places along this heavy outcrop of the St. Peters sandstone, need not the aid of imagination or fancy to shape themselves into dome and minaret, spire or cupola, or the graceful flutings, carvings, mouldings and columns of Gothic, Doric or Corinthian architecture. If well painted in oil, some of the more striking scenes would illustrate Illinois landscapes of no mean order of beauty. These bold, perpendicular bluffs of rock and deep ravines cut into them by the little streams, afford excellent opportunities for an ex- amination of the geology of this county, and will be again referred to in another part of this report. At Oregon and Grand DeTour good dams are built across the river, and a part of the magnificent powers thus obtained are made available for milling and manufacturing purposes. Dams might be constructed at many other points on the river within this county, and a supply of water-power be put into use unlimited in extent. Indeed, such a stream as Eock river, for water powers, is hard to find ; ' and some day it will enrich all this part of the State with its mills, manufactories, factories, founderies and machine shops. Other but smaller streams run through different parts of the county. On the north side of Eock river, and tributary thereto, is Leaf river and Pine creek. The former rises about Adeline, and among the gravel hills in the northwest part of the county, and flowing in 106 ECONOMICAL GEOLOGY OF ILLINOIS. a southeast course, mingles its waters with those of the larger river, a few miles below Byron. It is a considerable stream, and affords some fair water powers for light work. Pine creek runs into Rock river a short distance below Grand DeTour. It comes down from the north, making a sweeping bend towards the east. It is not a large stream, but, geologically, is one of the most interesting water courses we ever examined. On the south side of Rock river, the two streams of most note are Stillman's run and Kite river. The former is a small stream, rising in the eastern prairie townships, and terminating in Rock river a mile or two above Byron. Those familiar with the history of the Black Hawk war need not be told that this stream took its name from the retreat of a detachment of white soldiers under Major Stillman, after it had been ambushed and defeated by a band of Black Hawk's warriors. Those slain in crossing the stream were buried on a high point of land, near the residence of Joshua White, Esq. So long as the little stream flows, its historic name will pre- serve the name of that disgraceful scare and wild retreat from an almost imaginary danger. The latter is a more considerable body of water, originating mostly in the county, and coming in from a southeast direction. Its mouth is near the little village of Daysville. It is a slow, lazy stream. The country is rough, and more or less rolling, in close proximity to all these streams, except Stillman's run. The rough, hilly part of the county, along the streams, is covered with a fair growth of the usual white and 'black oak timber. None of it could be called heavy timber, and some of it is brushy barrens. Still, all these streams, with a few isolated groves, furnish a fair supply for fuel and other economical uses. The timber soil is thin and white, but under proper cultivation, returns good crops of potatoes, fruit, cereal grains, and garden pro- ducts. By far the largest portion of the county, however, is rich, undu- lating prairie land. All the eastern and southeastern part, all the western and northwestern part, together with much of the northern part, is prairie, as rich and beautiful as the State can produce. Whole townships are treeless. These prairies are covered with a soil composed of the fattest prairie loam. In a part of the State where all the counties are prosperous, Ogle will rank among the foremost ui agricultural resources and in the elements of material w r ealth. The amount of farm products annually raised and sold are enorm- ous, while the real resources of the soil are not yet half developed. OGLE COUNTY. 107 When these resources shall be more fully developed, and the vast untouched water powers of Rock river and its tributaries shall be utilized, this county will attain a degree of prosperity which will place it foremost in that richest portion of the Prairie State lying between Rock river and the Mississippi. Geological Formations. The geology of Ogle county is of a highly interesting character. Besides the usual surface deposits, the Galena, Blue and Buff lime- stones of the Trenton series, and the Cincinnati group, are all de- veloped and outcrop ; while the St. Peters sandstone for about four- teen miles along the river rises in bold outcrops of from twenty-five to two hundred feet in thickness. The only other outcrops of this interesting formation in the northern part of the State is at Starved Rock and Deer Park, on the Illinois river, and a few other points in LaSalle county. The following section will show the measured outcrops. They are all thicker, perhaps, than these figures indicate, except the St. Peters sandstone. The bottom of that formation and its full out- crop, we think, was reached. The floor of Rock river, three or four miles below Oregon, where its thickest development is reached, is the top of the Calciferous sandstone or Lower Magnesian limestone : Section of Ogle County Formations. Usual surface deposits, consisting of sands, clays, soils and gravel beds, aggre- gate, perhaps 125 feet. Cincinnati group, green and blue shales 25 Galena limestone , 35 Blue Trenton limestone 44 Buff Trenton limestone 36 St. Peters sandstone, white, soft 200 Lower Magnesian limestone The above figures indicate the maximum thickness of the surface deposits, the St. Peters sandstone, and perhaps the Buff limestone. The other members of the section I think are thicker than the above measurements indicate. Nowhere could I find exposures where the full thickness could be determined. Commencing at the top, we will describe these formations in their descending order. Surface Geology. The usual "river bottoms" exist along the streams to a limited extent. This, together with the common prairie soil, a vegetable mold, covering most of the county, comprises the extent of the Allu- 108 ECONOMICAL GEOLOGY OF ILLINOIS. vial deposits. The Drift formation is much more heavily developed. Over the southern and eastern portion of the county, and along the lower Rock river bluffs, it thins out to a considerable extent ; but over the northern and northwestern parts of the county the true Drift, in the form of drift-hills and coarse gravel-beds, is very heavily deposited, reaching a thickness, as we have above indicated, of one hundred and twenty-five feet. Over the parts first mentioned fine- grained clay, sometimes marly and sometimes sandy, cover the nether rocks. These clays are almost uniformly of a light-yellowish color. Few gravel beds and little coarse gravel can be noticed in passing- over them. Boulders are of rarer occurrence than in any other por- tion of this part of the State. It is not a driftless region, but the drift forces have acted peacefully here, and nothing but the finer sediments and precipitates of the water were here deposited or accumulated under the action of the chemical, atmospheric and aqueous agencies. But in the parts of the county last mentioned vast accumulations of coarse gravel, commingled with fine white sand, have been deposited, indicating that the drift forces and agen- cies acted here on a large scale. Around the head-waters of Leaf river these gravel hills are a marked feature in the landscape. About three miles and a half north of Forreston the Illinois Central . railroad passes through a range of these hills. The company have there opened many gravel pits and quarries, and are constantly loading trains for the^purpose of ballasting their road. The appear ance of that chain of hills is so remarkable that few travelers on the swiftly-flying passenger trains fail to notice and remark upon it. East of the track, a backbone of hills stretch away toward Adeline, broadening and widening in the distance, until they resemble great ocean waves fixed and solid. Our pocket-level showed that the highest hump on this backbone, measuring from the base, was about one hundred and three feet, while to the level of the water in the brooks, some distance off, the descent was probably twenty feet. The railroad track is cut through these gravel hills to the depth of about forty feet. For that depth the material is composed of gravel, from the size of pebbles to that of small boulders, mixed with a large quantity of white sand. The sand is almost as white as the St. Peters sandstone, except where stained yellow by the oxide of iron. The gravel is very much rounded and water-worn. The de- posit has marks of partial stratification in a few places. At one place, close to the railroad track, a bed of gravel, almost free from sand, is cemented so strongly together by some calcareous substance that it has to be quarried like ordinary stone. It looks like a coarse OGLE COUNTY. 109 conglomerate, or pudding stone, and will resist, without breaking, a smart blow from a heavy hammer. Such is the internal structure of these gravel hills. On the surface they are covered with a thin soil, full of gravel and whitish boulders of small size, in which a spade could not be sunk. Toward the east the hills preserve their outlines for a distance of some eight miles before they sink down into the ordinary gravel beds, extending for a long distance across the northern part of the county. Toward the west they extend three or four miles before losing themselves in the general roll of the prairies. The direction of the main chain is exactly east and west ; the western part, as indicated by a very good pocket compass, bears west southwest by east northeast. A little brook runs toward the east on either side of the gravel hills, being, perhaps, a quarter to a half mile apart. About the middle of the range, the brook on the north side breaks threugh an abrupt gap, and joins its sister on the south, and together they seek Leaf river, skirting along the south side of the gravel beds. To the north and south of the small valleys, through which these little streams flow, the prairie gradually rises until it attains almost the elevation of the gravel hills themselves. These hills resemble strongly the central moraines of a vast glacier, or where two glaciers meet and mingle in one ; but they also give evidences of the shifting and assorting agencies of water. They are, doubtless, "moraine hillocks," such as are found in many parts of Northern Wisconsin. If the surface of the underlying Trenton rocks could be examined over a dozen miles in extent in this locality, they would, we think, in many places be found plowed, grooved and scratched, or planed smooth by the slow, silent force of the irresist- ible glacier or iceberg. If the phenomena in this interesting locality indicate glacial action, and we think they most unmistakably do, it was probably combined with aqueous forces, and the two causes contributed to the results observed. We have sought for the manifestations of the glacial action in many places, while examining the drift through these counties; but while evidences of the floating iceberg and ice-floe, with their freight of boulders, of peaceful atmospheric and strong aqueous forces, are constant and recurring, this is the only locality where we could find phenomena that looked like the work of the glaciers. I examined with care the materials of which these gravel beds are made up. Much of it is composed of metamorphic rocks, brought from the regions of Lake Superior. But a large portion, from one- 110 ECONOMICAL GEOLOGY OF ILLINOIS. third to one-half perhaps, is derived from the Niagara, Galena, and such other limestones as are found in the Lead Basin. They are much rounded and water- worn, but are not transported from the great distances from whence came the granites, syenites, and other boulders and gravels. Tentaculites, from, the Niagara ; fragments of Orthocera and Orthis, from the Blue ; Pleurotomarias and pieces of Trilobite shields, from the Galena, were noticed among these piles of gravel imperfect as fossils, of course, but sure indications of the neighboring formations from which they were derived. A mixed mass of gravel, like the one under consideration, would seem to indicate that forces from a distance and forces near at hand, operating in every conceivable direction, with great force and over long periods of time, all contributed to gather together these heaps of abraided materials, some from the distant regions of the granite .and the traps, and some from the neighboring limestones of a by-gone geological age ; but all equally worn smooth by the grinding of the waters and ice. But, leaving this interesting accumulation, we still find evidence of the Drift gravels all over the northern part of the county ; but the beds become comparatively thin, and are underlaid by the usual clays of this part of the State. The blue clay, belonging to the base of the Drift, we failed to detect through Ogle county. It doubtless exists if proper excavations were made, but the common light-colored yellowish clay is by far the most common. Remains of the Mastodon have been found closely connected with this formation. In 1858, the tooth of one of these animals was found in a little tributary of Stillman's run. The locality is low somewhat marshy. The stream has cut a channel through the black alluvium of the low prairie. The tooth was washed out and lodged against a clump of willows when found. It is a ponderous grinder, weighs seven and one-half pounds, is covered with a black shining enamel, and is a fine fossil in a high state of preservation. The fortunate finder carefully preserves it, and cannot be induced to part with his treasure. Other Mastodon remains doubtless exist about the marshy springs of Stillman's run. Some years ago a large bone, supposed to be from the fore-leg of one of these animals, was found two or three miles above Byron. The bank of Rock river had caved down for some distance back from the stream ; some five feet below the surface of the highland coming up to the river, and perhaps fifteen feet above ordinary water-level, the bone was found sticking in the bank. The bank OGLE COUNTY. Ill seems to be a sort of a modified drift, made up of somewhat marly, dark-colored alluvial clay, intermixed with river sand and a con- siderable quantity of gravel. The formation is hardly alluvium, but seems to be a kind of a river drift. The fossil is light, porous, and whitish in color, in a rather poor state of preservation. We obtained it through the courtesy of Mr. Mix, and sent it to the State Geo- logical Cabinet. Among the mineral substances found in the Drift of this county, bits of lead and pieces of pure Lake Superior copper are occasionally met with. The Cincinnati Group. This formation is but lightly developed in Ogle county. No exposed outcrop, that we are aware of, exists at all. The high prairie, however, east and northeast of Polo, lying between Pine creek and the Illinois Central railroad, extending a few miles north towards Adeline, is underlaid by the shales of the Cincinnati group. At several recently dug wells, piles of these cream-colored and blue shales and clays attracted our attention. They are generally struck at a depth of fifteen or twenty feet, and soon crumble to pieces when exposed to the rains and frosts, and other atmospheric influences. The exact thickness of this group I am unable to state, but think it exceeds rather tha^n falls below twenty-five feet. The area indi- cated is covered by the usual light-colored, finely comminuted clays, which nearly always rest upon the rocks of this group. It generally forms the subsoil of a good agricultural region, but sometimes it is inclined to be a little too sticky and wet. Ever-living wells of reasonably pure water are found without difficulty wherever the Cin- cinnati shales lie near the surface. In some cases, masses of sticks and decayed drift-wood lie between the shales and superimposed clays, separated from the former by only a few feet of marly, black- ish clay. In such cases the water of the wells is neither sweet nor pure. The Trenton Group. The Galena Limestone. Next in the descending series comes the upper division of the Trenton group, known generally in the books as the Galena limestone. It underlies a considerable portion of the county, emerging along the face of the ravines from beneath the concealing Drift, and even rising like mural walls along some of the streams. The line of demarkation between this and the nether Blue 112 ECONOMICAL GEOLOGY OF ILLINOIS. limestone is not always easily distinguished. Layers, partaking of the characteristics of each of these divisions, are often found inter- mingled for some distance, although the characteristics of the mass of the two formations are very distinct. This peculiarity is not so marked in this county as in the eastern part of Stephenson. The rock here usually preserves its usual coarse-grained porous nature towards the top of the quarries, changing into a denser sub- crystalline mass towards the bottom of the formation. It preserves its usual dull, greyish, cream-colored, chrome-yellow tints. No out- crop of it appears along the banks of Eock river, unless it may be near the Winnebago county line. But as we go back from the river the older formations sink down and run under, and this becomes the prevailing surface rock. It is an important member of the series of Illinois strata, both on account of its many economical uses, its historic interest, and the lead-bearing character of certain portions of its basin. The superficial area underlaid by the Galena limestone in this county is quite large. South of Eock river the older formations come to the surface a few miles back from the stream, and outcrop along the ravines cut down into this belt of rough rolling country. But the Galena runs on almost as soon as the level ^prairie is struck ; and all the eastern and southeastern townships are underlaid by it. and would show it, could the concealing drift clay be removed. The township of White Eock takes its name from a* low outcrop of light- colored Galena about the headwaters of Stillman's run, near the center of the township. It is quarried to some extent, and hauled over the surrounding prairie. The stone is rather soft and crumbly, but is used extensively by the farmers for cellar walls, foundations and other similar uses. Kilbuck creek running north through the southeastern portion of the county, cuts into the same rock and even touches the Blue limestone, but no good outcrop is shown. About Payne's Point, in the township of Pine Eock, along a little timber ravine, stones are quarried whose conchoidal fracture and ash-color show beds of passage between the Galena and the Blue. North of Eock river the same phenomenon is observed, only on a more extensive scale. The older formations sink as the distance from the stream increases, until the Galena runs on, forming sur- face rock where the river enters the county, but, before reaching Byron, it strikes these older formations. Leaf river and Pine creek cut deep into the surface deposits, and show outcrops of the St. Peters sandstone, the Buff and Blue limestones respectively for some distance after the Galena becomes the underlying rock of the sur- OGLE COUNTY. 113 rounding country; but even along the banks of these streams, the Galena outcrops long before their sources are reached. All round the headwaters of Leaf river the gravel beds rest directly upon the Galena limestone. The road from Polo to Mt. Morris crosses Pine creek about the middle of its course. At the crossing, Galena escarp- ments, crowned with the white pine and red cedar, overhang the creek as it washes their base. In going down stream the Blue Tren- ton is soon struck ; but in going up stream, even to its very sources, massive time-worn outcrops of the real lead-bearing rocks add pic- turesqueness to the scenery. At the forks of Pine creek, a few miles northwest of the residence of Hon. D. J. Pinckney, there is an out- crop thirty-six feet thick, the upper half of which is quarried into. A lime-kiln is here in successful operation; and stone is quarried for common building purposes. The western part of the county, between the Illinois Central rail- road track and the county line, is principally underlaid by the lime- stone under consideration. Elkhorn creek, which just touches the county about Brookville, and Buffalo creek, a small stream west of Polo, both cut into the Blue limestone as the exceptions to the above statement. At the quarry one mile west of Polo, on the Mt. Car- roll road, the Galena composes the top layers; the middle is beds of passage, and the bottom is the Trenton Blue. Following the creek down past the large Blue limestone quarries southwest of Polo, the Galena is again struck before the county line is reached, and at Sanfordsville, a short distance beyond the county line in Whiteside county, displays itself in a massive quarry, worked exten- sively in former days. The same rock prevails about Woosung. At White Bock and at the forks of Pine creek a few characteristic fossils were to be seen ; but the rock is not worked enough in this county to afford many fossils or good specimens. Where a Galena quarry is extensively worked for months at a time, and carefully examined during all its working, fossils worth gathering may be found ; but a visit of a few hours to outcrops little worked at the time, cannot be very satisfactory so far as the acquisition of fossils is concerned. The Blue Limestone, This, the Blue limestone of the Western geologists, or the Trenton limestone of the New York survey, is, under present classification, the Blue or Middle Division of the Trenton proper. In a descending order it next succeeds the Magne- sian beds of the Galena division. It is variable in appearance. The upper parts of its outcrops are thin-bedded, almost shaly, and of a 8 114 ECONOMICAL GEOLOGY OP ILLINOIS. buff or lead-white color, often breaking into fragments when quar- ried. The lower layers are compact and thick enough to make a good building stone. They break with a glassy fracture; and some of the layers near the bottom are of a deep ultra-marine blue-color. This fine color fades a shade or two lighter when the stones have been quarried and exposed to the weather. In the region of country underlaid by this rock, pit-holes, or sink- holes, are of frequent occurrence. These curious depressions in the face of the country are from one to three rods in diameter, and run to a point in a funnel- shape, at a depth of from six to fifteen or twenty feet. The rock also contains vertical crevices, through which subterranean streams of water often rush after heavy rains or springy thaws. Along Buffalo creek, west of Polo, for three or four miles, there is an upheaval of the Blue limestone. The top of the first quarry, the one on the Mt. Carroll road, as already stated, is composed of Galena limestone, shading down into beds of passage into the under- lying division; but the bottom is the genuine blue "glass-rock" of the Trenton. Two miles below this, on the creek, several other quar- ries are opened and heavily worked. They, and in fact all worked exposures of this rock examined in this county, show substantially the following section : Feet. Chocolate-colored clays and subsoils, with fragments of rock and some gravel 5 Thin-bedded, buff-colored, fragmentary limestone, sometimes light lead-colored 14 Heavy-bedded, blue, glassy layers, breaking with a cloudy, conchoidal fracture 6 These Polo quarries are worked to a depth of about twenty-five feet. The blue layers in the bottom are sometimes a foot thick. When lifted from their watery bed, they look as if dyed in blue ink. A large public school house is now building in Polo from stone ob- tained at this locality. The blue color is conspicuous, and the effect striking and beautiful. This limestone also outcrops about Brookville and west of Forreston a short distance, where it is quarried on some of the small feeding streams of Elkhorn creek. On the map of Ogle county I have marked, in colors, several long narrow strips on either side of Rock river. They extend diagonally nearly across the county, preserving the general course of the stream. The broad blue band represents the part of the county along the stream underlaid by the Blue limestone. All the small streams falling into Rock river from both sides, so far as I examined them, present the following succession of the rocks. At their mouths, especially from three miles above Oregon to Grand de Tour, the St. OGLE COUNTY. 115 Peters sandstone comes to the surface ; a short distance up stream the Buff limestone outcrops along the banks and on the sides of the ravines ; farther up, the limestone under consideration is met and continues to outcrop for two, three or four miles ; then the Galena rises like a rocky wall along the waters' edge, and continues the sur- face rock until the headwaters of the streams are reached. Some of the hillsides show all three of these resting conformably upon each other, as in the ravines about Oregon, and along the lower part of Pine creek. Kite river and the next stream below it south of Eock river, Leaf river, Pine creek, and almost any of the small brooks, present the same succession of the rocks. On Pine creek, from a mile below the croseing of the highway leading directly east of Polo, to about Sharp's mill, the upper thin- bedded layers of the limestone under consideration outcrops in rocky- faced abrupt bluffs, reaching a thickness of forty or fifty feet. The heavier blue layers of the Polo beds were not here observed. They resemble the outcrops of the same rocks above Dixon, except that fossils are rare, and the rocks have a dry, baked appearance. At Sharp's mill, the St. Peters sandstone and the Buff limestone begin to outcrop along the base of the hills. Above Byron the river hills are capped with the Blue, changing into the Buff towards their bases. The Blue limestone at Dixon and many other places is full of fos- sils. Slabs of thin stones are there found covered so thickly with fragments of small trilobites, corals, stems of encrinites, and mollusca of various genera and species, that one cannot help wondering at the great abundance of the lower forms of animal life which swarmed in the ocean of the lower Silurian era. These thin fossiliferous strata are compact and solid, and when dressed and polished look like a beautiful variegated marble. Dr. Everett, of Dixon, has in his cab- inet specimens of this polished marble, which will compare in beauty with any marble we ever saw. In Ogle county, however, we could nowhere find in the'Blue limestone the same abundance of fossils. At Polo, a large chambered shell, known there as an Ammonite, but probably the Lituites undatus of Hall, is occasionally found ; also an Orthoceras, which sometimes reached the great size of nine inches in diameter and eight or ten feet in length. But the thin fossiliferous layers, such as are found at Dixon, were not found. A heavier working of the outcrops along Pine creek might disclose them. A barrenness of good fossils seems to characterize all the formations in Ogle county. 116 ECONOMICAL GEOLOGY OF ILLINOIS. The Buff Limestone. The lower division of the Trenton, or the Buff limestone of OWEN, next succeeds in the descending order. It crops out in many places in close proximity to the St. Peters sand- stone. In some places it is separated from the overlying division by a few feet of shale and blue clay ; in others the transition from the one to the other is not easily distinguished In the former, it is thick- bedded, compact, and the heavy layers are divided by thin fossilif- erous layers and thin blue bands of clay; in the latter it is shaly, shingly, yellowish-buff-colored, resembling much certain parts of the Blue division. . Dr. Everett's description of this rock corresponds with my own observations, so far as outcrops in close proximity to the St. Peters sandstone were examined. In the ravines above and opposite Oregon; at Sharp's mill, on Pine creek; at Moore's quarry, in Lee county; on Kite river, and in one or two other places, this is true. At Sharp's mill and near Oregon, the lower layers are of a dull e'arthy-color and fracture, with considerable sand in their com- position, and, on being struck with the hammer, give a heavy dead sound or thud, as if striking a mass of frozen earth. This description would hardly apply, however, to the outcrop at Byron. This corresponds exactly with WHITNEY'S description of the Buff limestone outcrops at Winslow and Beloit; and these are ex- actly like many outcrops of the Blue division, except that the fossils do not seem to be identical. Fossils. At Moore's farm, in Lee county, many fossils were observed, mostly imperfect casts on the thin layers of shaly matter, sepa- rating the massive layers, and also on the surface of some of the massive layers. But in the Ogle county outcrops we could hardly detect a fossil, except at Byron. There we found a part of a large Orthoceras, six inches in diameter, perhaps. The animal to which it belonged must have been six or seven feet long. The St. Peters Sandstone. This very interesting formation outcrops heavily in this county. It is the prevailing rock along Eock river, from about two and one- half miles above Oregon to three miles below Grand De Tour, a distance of about fifteen and one half miles. Where the bluffs and high land come up to the river, this rock nowhere outcrops more than a mile or two back from the stream. Even the river bluffs, along the sandstone region, in places, are capped by the limestones of the upper Blue and Buff. But up the tributary streams low out- OGLE COUNTY. 117 crops may be noticed extending miles back from Kock river. Up Pine creek it may be traced as high as Sharp's mill, some five miles from the river. Up Kite river, for perhaps as great a distance, it shows itself along the base of the bluffs and hills, often just above the water's edge. Up the smaller streams it can be traced lesser distances. Many of these hills I have found capped with the Blue limestone lying upon the sandstone unconformably ; many others exhibit the Buff and Blue lying upon each other conformably; some are capped by the Buff alone ; some are nothing but hills of sandstone, uncapped by even the overlying drift, weathered into shapes resembling the pictured icebergs of the Arctic seas. The high bluffs, at the base of which the town of Oregon stands, with the exception of a light limestone cap on the top, are composed of light- colored St. Peters sandstone. At this locality it is about one hundred feet thick. It rapidly dips for two miles and a half up the river, and finally runs out of sight, the last outcrop observed being half a mile up a little stream, and about twelve feet thick. As we go down the river, the thickness increases. About four miles below Oregon, at the fantastic shaped "Indian pulpit," the sandstone peaks rise higher than at Oregon, and before the mouth of Pine creek is reached, the elevations measure from one hundred and seventy-five to two hundred feet. After reaching the mouth of Pine creek, the forma- tion dips rapidly, and soon runs under the overlying formations. Two or three miles above Oregon, on the other side of Kock river, the bluffs rise in a long line along the stream to a height of, per- haps, one hundred feet. The debris and talus of these hills present an abrupt, grass-covered slope to within twenty feet of the top. The rest of the height is a long, low, beetling mural escarpment of frowning Buff and Blue limestone. The talus covers the St. Peters sandstone, which doubtless forms the base of the hills. Opposite Oregon, in a low hill, a sandstone quarry and a Buff limestone quariy exist within a few rods of each other. Peculiarities noticed while examining this interesting sandstone suggest a few observations. In many instances hard metallic-looking layers, or bands, like the red carnelian bands in the trappean rocks of Lake Superior in their modes of occurrence, are found running in somewhat parallel planes through the softer material of which this sand-rock is composed. These are from one-half an inch to two inches in thickness, and are often within a few inches of each other. As the softer material crumbles away these remain projecting, giving the rocky face of the outcrop a pictured or horizontally veined appearance. The frost 118 ECONOMICAL GEOLOGY OF ILLINOIS. breaks these off, and they accumulate in the ravines. They give a hard and ringing sound when struck with the hammer, and almost resemble pieces of old castings in both color and hardness. These layers are ferruginous in texture, and were formed by the oxide of iron cementing together and hardening thin layers of the sandstone while in course of being deposited. At a little ravine between Ore- gon and Mt. Morris they lay in piles, as if an old pot foundry had once existed there. At the crossing of a small stream between Dixon and Daysville, where an old mill-dam had once been built, and a low outcrop of red St. Peters sandstone may be noticed at the right of the crossing, they lay over the hillside and in the road in great abundance. On many of them, ripple-marks, as perfect as when made in the soft sand of the old Silurian beach, still exist. They are the eddies and ripples of the Silurian seas turned to fossils, and preserved in the embrace of iron and sand. Again, these sandstone hills resist atmospheric agencies in a won- derful degree, considering the soft and friable nature of their compo- sition. Oftentimes, where they are most abrupt, one can pick holes in their perpendicular sides with his knife, or strike his pick into the solid-looking mass. One would expect that such masses would crumble to pieces and sink into low white sandbanks, but such is not the case. They preserve their forms as well as the limestones, and have quite as little debris and talus piled about their bases. The color of this sandstone is of all shades, from the whiteness of crushed sugar to chrome yellow, and the many tints of brown and red. The color is a stain produced by the oxide of iron held in solution in the waters, which have at various times percolated through the sandstone mass. Where this dye was absent in the percolating water, a sandstone as white as granulated snow was the result; as the dye was present in the water, in that proportion are the sandstones colored and stained. In consistence this sandstone is saccharoidal, or sugary, and much of it is held together by the slightest cohesive attraction. In many places, especially where the sandstone was very white, I found diffi- culty in obtaining cabinet specimens. Every blow of the hammer would shiver the block to pieces. But .this is not always true. I saw houses built from this material which seemed to be hardening into a fair building stone ; and Dr. Everett gives an account of an arched railroad bridge built over Franklin creek, in Lee county, from the same sandstone. In a few places it seems to have become hard and crystalline ; in a few more it has cohesion enough to make OGLE COUNTY. 119 an indifferent building stone ; but its general character is soft, friable and uncohesive. Under a strong microscope the grains of the white variety ap- pear limpid and semi-translucent, those of the darker varieties as if coated over by rust. All the grains are round, similarly formed, and similar in size. The grains are quite small, and the mass is remarkably pure and homogeneous in character. These incoherent, crystalline grains of transparent quartz owe their darker colors, where colored, to a solution of the coloring matter held in chemical combination ; but in most cases the color is caused by a formation over the surface of the siliceous grains of sand. Distinct stratification exists in most of the outcrops, and even lines of cross stratification are not rare. WHITNEY failed to notice wave marks in the Wisconsin outcrops ; but there can be no mistake as to the wave and ripple marks on the ferruginous layers of the Eock river outcrops. Some of the large masses present abrupt and strong dips ; but these are owing to local causes. No trace of organic life, either plant or animal, has yet been observed in these sand- stones. The era of their deposition seems to have been a peculiar one. Great changes must have taken place as, it was ushered in and as it went out. A high axis of elevation runs along this heavy deposit. . In* either direction from the river it dips away rapidly, and the overlying de- posits come on in quick succession. Bock river runs along this anticlinal axis, having cut down almost or entirely through the form- ation. The heaviest outcrop of the deposit now under consideration, in the whole area over which it is known, is the one along Eock river in Ogle county. The formation is thin and wide-extended, embracing a superficial extent in the northwest alone of more than four hun- dred miles in length by over a hundred in width. At Starved Eock, on the Illinois river, it is about one hundred and fifty feet thick. In Calhoun county it outcrops in the Cap-au-Gres Bluffs to a thick- ness of perhaps eighty feet. In Wisconsin and Minnesota its heaviest outcrops do not much exceed one hundred feet in thickness. In Ogle county, however, we think it reaches fully two hundred feet, and at the artesian well in Stephenson county it is perhaps consid- erably thicker. It is the identical same rock known in the Missouri Eeports as the Saccharoidal sandstone, so extensively used in the manufacture of glass at Pittsburg. As observed in Missouri, how- ever, it is oftener of a light buff or brown color, and has less of 120 ECONOMICAL GEOLOGY OF ILLINOIS. the white, pure siliceous sand in its composition than the same rock has in Illinois and further north. Geologists seem to be greatly in the dark as to the origin of this curious, interesting formation. The Lower Magnesian Limestone. The lower Magnesian limestone, or Calciferous sandstone of the New York geologists, or its Western equivalent, comes, I think, to the surface at several places in the bed of Kock river, between Oregon and Grand DeTour. The floor of the river in many places along these high sandstone bluffs, I am quite sure, is a harder, solider, and altogether different rock. When doing field-work in that part of the ground gone over by me, I had poor facilities for exam- ining the river bed; but at one locality on the north bank of the stream, five or six miles below Oregon, and just at the edge of rather low water, I found a stratum of stone, apparently in situ, which I believe to be the top of this formation. I confess, how- ever, that my judgment as to the existence of the lower Magnesian limestone along the river-bed in this county is formed, at least partly, from analogy, appearances, and the natural belief that the bottom of the St. Peters sandstone is here reached. A proper ex- amination of the river-bed, or some shallow borings along its shores^ would satisfactorily test the matter, and settle any existing doubt. Economical and Agricultural Geology. Most of my remarks upon the economical and agricultural geology of counties north of this one would apply with equal correctness to Ogle. In physical features, geological formations, and agricultural capabilities, they have much in common. There are some points of difference, however. Stone for Economical Uses. All the limestones afford a good build- ing stone. The seminary building at Mt. Morris, and the new public school at Polo, are fine examples of the building materials furnished by the Blue limestone quarries. The rock is not only strong, easily worked, convenient to obtain, but when properly laid up of blue, or mingled buff and blue colors, the architectural effect is beautiful. The thin-bedded top layers furnish a good stone for the lighter in- dustrial uses. The heavy-bedded, dull-colored buff is more used for the heavier kinds of masonry. The Galena in this county is a rough, thick-bedded stone, used in cellar walls, bridge foundations-, and the common stone work necessary on the farms about its out- OGLE COUNTY. 121 crops. In a few places the St. Peters sandstone has crystalline layers of sufficient tenacity to cut into window and door caps, build into cellar walls and dwelling houses ; and in one instance, at least, is used for the culverts in a small railroad bridge. It is easily hewn into shape, and seasons into great hardness and tenacity. Certain layers of the Blue limestone also burn an excellent com- mon lime. The kilns above Dixon, in Lee county, turn out an abundance of as good lime for ordinary building purposes as need be desired. The sub-crystalline layers of the Galena are well adapted for lime production, and are much used for that purpose. On Pine creek, timber is abundant ; stone from both these divisions is easily obtained, and of good quality; and lime can be made in any desired quantity. It is generally believed that some layers of the Buff might be burned into a good hydraulic lime ; but this is not known by the test of experiment. Peat. On the Kilbuck creek, on section 30, in the township of Monroe, there is a long, narrow, irregularly shaped peat bed, con- taining about fifty acres. In the deepest parts the deposit is, per- haps, twelve feet thick. The peat is the result of the decay of the usual grasses, sedges and mosses, but is rather grass-peat than moss-peat. Compared with the Cattail beds of Whiteside county, it is more porous, fibrous and unripe. It is available already as a fer- tilizer, and like the rest of our small, prairie, unripe beds, will some day be used largely for that purpose. Its value, as a fuel, depends upon the success of the peat experiments now being tried in many places. For a fuller discussion of Northern Illinois peat, its eccnomical uses, its value, and its future prospects, I refer the reader to the report upon the economical geology of "Whiteside county. Clays and Sands. Banks of common yellow sand, suitable for mortar making and plastering, may be found almost anywhere in the banks and sand-bars of Eock river. The subsoil clays under the thin oak soils, and in fact most of the sandy subsoil, may be molded into a good article of common red brick. According to all our Western geologists, the white rocks of the St. Peters sandstone furnish the very best material for the manu- facture of glassware. The Pittsburg glass manufactories obtain tons of their sand from the saccharoidal deposits of Missouri, a rock identical with our St. Peters sandstone. Our sandstone, however, is white, pure, limpid, and free from foreign matter; theirs consist more of the yellow and brown-stained varieties. The sugary, white 122 ECONOMICAL GEOLOGY OF ILLINOIS. sandstone of the upper Mississippi is a pure silica. If the state- ments of the learned Dr. OWEN are true, only about two-tenths of one per cent, of extraneous matter, as shown by chemical analysis, enters into the composition of the snow-white sands of this forma- tion. Thousands of tons of the sand could be cheaply transported down the river to the Rock Island coal fields ; or, when the contemplated railroad up the Rock River valley is completed, for the purpose of connecting the lumber regions of the north with the prairies of Iowa and the coal fields of Illinois, the coal could be easily run up from Rock Island to the Oregon or Grand DeTour sand cliffs, and glass- ware for the whole Northwest be cheaply and successfully manufac- tured. These facilities for moving the coal and sand together will exist at no distant day. It will then remain for capital to invest in this remunerative branch of manufacturing industry. Soils and their Products. The dark-colored loams are underlaid by a light-colored, clayey or gravelly subsoil. The loam is largely composed of vegetable elements. If not made up of, it is at least greatly enriched by the successive growth and decay, for ages, of our common prairie grasses. This is the soil of our prairies. The timber soils are the usual clayey deposits of the oak ridges, underlaid by a close, compact, yellow subsoil. Hungry, sandy soils are seldom met with. Leachy, loamy, fat soils, well adapted for the best farm- ing lands, cover most of the county. The soils in this portion of the State are composed of silica, or the earth of flints ; alumina, or fine impalpable clays ; carbonate of lime, or calcareous materials, making marly soils ; and various other materials, such as the oxide of iron, organic matter and the like. The two first are the basis of all our soils. The last gives them fertility. No soil is composed of a single one of these elements ; but the mixture or chemical com- bination of all these, and sometimes many other elements, exist in the same soil, making clay soils, clay loams, loamy soils, sandy soils, vegetable molds, marly clays or sands, and many other kinds of soils, well known to agricultural chemistry. I think the general proposition is true, that where large tracts of country are underlaid by the same or closely related geological formations, the soils will have some resemblance to those forma- tions. They are undoubtedly, in part, derived from them; and in many cases in this part of the State, as I have already intimated, the soils and subsoils seem to show their origin from these subja- cent rocks. But this remark must be received with considerable al- lowance. The transporting, sorting, and sifting agency of water, the OGLE COUNTY. 123 ice action of glaciers and icebergs, and the evidences that other geological forces have been at work all over this region, leads us to greatly modify the statement just made, and to believe that our soils are, in part at least, derived from many sources some of them remote from their present localities. The same is true, I think, of the subsoils, and finer materials of the drift. These, originally per- haps, were all alike ; but chemical and atmospheric agencies and the growth of vegetation changed the surface clays into rich fat soils; the subsoils received less of these influences, but still felt them, and were further changed by the percolating, saturating surface waters ; but the deep lying clay and sandbeds received no change from these agencies. Even the acids of the air could not penetrate to them, and they remain unchanged. Ogle county shows more evidences of a transported soil than west- ern Stepheuson or Carroll county. Geology, engaged in investigating these phenomena, is thus the handmaiden of agriculture, and ought to be encouraged and studied by the farmer. He should not be slow to learn that all branches of human knowledge are bound together like the links of a chain; all the arts of life sustain to each other dependent relations, and all cultivators of soil or science ought to be bound together by the bonds of a common interest. But, however derived or made up, the soils of this county are generous and fertile in a high degree. Indian corn, wheat, oats, hay, potatoes, barley, rye, the products of the kitchen garden, the hardier fruits of garden and orchard, are here raised in bountiful profusion. Vine culture has not yet attracted much attention, not for the want of suitable localities in which to try the experiment, but simply because attention has not yet been directed to this branch of horticultural industry. In speaking of these noble soils the Edens of agriculture in these Western States I may as well make some remarks here, which ap- ply with equal force to the agricultural policy of this and all the neighboring counties, and to the practices of prairie farming gener- ally. I mean the unscientific, slovenly, and wasteful modes of cul- tivating the virgin soils of our broad prairies. The unripe peat and muck remain undisturbed in their beds ; trenching and subsoil plow- ing are never resorted to ; annual fires consume the surplus stubble and stalks left from the last year's crop ; ashes, bones, lime, the barn-yard and stable manures, if disturbed at all, are raked into some convenient out of the way place ; and the farmer generally cultivates so much that he cannot half cultivate anything at all. 124 ECONOMICAL GEOLOGY OF ILLINOIS. Geology and chemistry, and the experience of older countries, all cry out against this wrong done to our generous soils. In the first place, the farmer ought to study his soil, ascertain what element is wanting or what it has in excess, and intelligently supply the one or counteract the other. Instead of scratching over a large amount of soil, if he would go deeper and throw up a little subsoil, the kiss of the roving winds, the rain and the sunshine would enrich these, and his soil would grow deeper instead of becoming hungry and ex- hausted. Composts should yearly be made of every available sub- stance, and scattered with a profuse hand over his meadows and grain-producing fields. Perhaps some water-soaked bog and some unproductive ridge, lying side by side, and both worthless, have in them the complements of the best producing soils, and only need a little mingling to make them the most valuable tracts in the field or on the farm. A little mind employed in cultivating the earth is better than much manual labor, aided though ft be with all forms of labor-saving machinery. Against this wasteful system of farming every industrial interest should cry out. Our soils, when new, used to return average crops of forty bushels to the acre; now fifteen is a good crop on the older cultivated lands. In the corn field, seventy, eighty, and one hundred bushels to the acre was not an unusual yield; now thirty- five or forty is oftener the exception than the rule. At this rate our land will rapidly become exhausted. Good husbandry, good farm- ing, if not able to keep the soil up to its primitive fertility, ought, at least, to prevent its rapid deterioration. CHAPTEE VIII. LEE COUNTY. Lee county is bounded on the north by Ogle, on the east by DeKalb, pn the south by LaSalle and Bureau, and on the west by Whiteside. It is a large county. Its longest extent from west to east is thirty-six miles, and from south to north is twenty-two miles. It contains eighteen full townships of land, and a little over four half, townships, embracing in all about seven hundred and twenty- eight sections of square miles. The face of the country is diversified, and is made up of rough, hilly land, broad and level prairies, and extensive swamps and marshes. The Winnebago swamps, in the southwest corner, and the Inlet swamps east of the center of the county, are peculiar features in its topography, and will receive a farther notice in a subsequent part of this report. The northwestern part of the county, where Eock river cuts across the corner, is rough, hilly and in places picturesque, especially in the vicinity of that stream. The hills and ravines in this locality are partially covered with dense underbrush and scat- tering timber. The rest of the county, with the exception of an occasional grove, is a broad, level, fertile prairie, inclining in some places to be rather low and wet. Such is the character of the prai- rie land in places in the eastern part of the county, and also along its western and southwestern borders. The agricultural resources and grain-producing capabilities are very great, owing to the large amount of excellent farm land in the county, while the wet lands afford good grazing, pasture and meadow farms, and make stock- raising a very successful and remunerative business/ Timber is scarce. Sugar Grove, Lee Center Grove, Melugin's Grove, Pawpaw Grove and a few smaller groves, and the scattering bodies of timber along Rock river, afford about the only supply. The oaks, 126 ECONOMICAL GEOLOGY OP ILLINOIS. walnuts, sugar-maple, linden or basswood, and hickory, are the pre- vailing kinds of timber, although almost every kind in the catalogues for Northern Illinois may be found in the groves. Rock river and the railroads make the pine lumber of the north of easy access to the people of this county, and they do not feel this want of timber as do some of the neighboring counties. Hedges are also grown to considerable extent, and dispense with much fencing lumber. The osage orange here makes an excellent fence when properly planted and taken care of. The history of this plant is' peculiar. Many years ago it was extensively introduced in Northern Illinois. Miles of it were planted in hedges. There was great faith that it would prove an excellent fencing material, but the hedges were poorly planted and suffered to take care of themselves. As a natural con- sequence, poor cultivation and several hard winters caused the hedges to fail as fences. For several years the osage orange attracted little attention as a fencing material; but in the course of time, a few hedges that had been properly cultivated grew into beautiful and suc- cessful fences, and public attention was again turned to the osage orange. Miles of excellent fence may now be seen in these northern counties, and hundreds of miles are planted every spring. Instead of the few rows of straggling, ragged, unevenly-grown bushes which used to deform the landscape, long lines of well-grown, compact, green, shining walls of the hedge plants may now be seen, which would defy a buffalo to break through them. Hedge-growing and timber-growing are not geological questions, but they are great material interests, which are now attracting much attention. Eock and Green Eivers, and the upper portion of Big Bureau creek, are the only streams of consequence in the county.- All these flow in the same general direction, and almost parallel to each other. The general course of these streams is from northeast to southwest. Rock river strikes the county at Grand DeTour, about twelve miles east of the northwestern corner of the same, and cuts of? about two townships from the northwest corner. From Grand DeTour to Dixon the bluffs approach closely to the river are bold, rocky and precipitous, cut up with ravines, and show excellent out- crops of the several formation of Silurian rocks. Below Dixon the bluffs gradually recede and grow lower, and finally swell away into undulating prairies of great beauty and fertility. Green river is not a river, or even a stream, for a portion of its course across the county. It takes its rise in the swampy land in the eastern part of the county, and in the Inlet swamps between LEE COUNTY. 127 the eastern and central parts of the county. The surplus waters of this Inlet swamp, two or three miles southeast of Lee Center, are gathered into the first well-defined stream or current of Green river. For ten or twelve miles the stream flows southwestward, and again becomes lost in the interminable Winnebago swamps, in the southwest part of the county. Along its whole course there are no bold bluffs, no distinctive river valley, and no outcropping rocky formations, except about Lee Center, where some low outcrops of the Galena limestone are quarried. Big Bureau creek, in the southeastern part of the county, is a prairie brook, with no marked peculiarities. Several small creeks and brooks, such as Sugar creek, in the township of Palmyra, and Franklin creek, east of Dixon, are worthy of notice. The latter is one of the most interesting little streams in the county. It exhibits in its short course a fine section of the geological formations in this part of the county. Geological Formations. These are varied and interesting. Below the superficial deposits, we commence with the. Niagara limestone, and go all the way down to the St. Peters sandstone. A section of the geological formations of the county, in the order of their sequence, would be represented by about the following figures : Feet. 1. Drift deposits 10 to 75 2. Niagara limestone 3. Cincinnati group 30? 4. Galena limestone 25 to 70 5. Blue, or Old Trenton 20 to 75 6. Buff limestone 18 7. St. Peters sandstone 150 Reversing this order, I propose to commence at the bottom, and describe these formations in the ascending order. The St. Peters Sandstone. This very interesting rock underlies a very considerable portion of the county, and outcrops heavily on Bock river and Franklin creek. The heaviest outcrop in the county is opposite Grand DeTour, just across the river. The base of the bluff, for thirty or forty feet upwards, shows this rock. Here it has a solid, unstratified look, and rusty-brown color. On the Ogle county side of the river the sandstone is whiter, and the outcrop is over one hundred feet in thickness. For two or three miles the bluffs are mostly composed of this material. Just below the mouth of Pine creek the formation on Bock river sinks rapidly out of sight, and is succeeded by the Trenton limestones. On the Lee 128 ECONOMICAL GEOLOGY OF ILLINOIS. county side of the river the sandstone soon disappears, after leav- ing the outcrop opposite Grand DeTour. Between the latter place and Dixon fine outcrops of Trenton limestone occur. The St. Peters sandstone on Eock river, as will be seen by a reference to my report upon the goology of Ogle county, is chiefly developed in the latter county. For a distance of about fourteen miles, commencing about two miles above Oregon city and terminating a short distance below the mouth of Pine creek, it is a very marked feature of the Eock river bluffs. The outcrop extends back but a short distance from the bluffs. In some of the ravines and intersecting streams it can be traced for one, two or three miles. On the east, north and west of these sandstone bluffs the formation terminates abruptly, sinks out of sight rapidly, and seems like an abrupt, anti-clinal axis pushed boldly up into the air. On these sides the overlying formations are piled as it were against the sides of this sandstone uplift. But on the south side it sinks away more gradually, and doubtless is the underlying rock for most of the distance in a south- east direction to the great upheaval at Deer Park and Starved Eock, on the Illinois river. A line drawn from the mouth of Franklin creek up that stream, thence on a southeast course to the south- east corner of Lee county, and thence to the Illinois river through LaSalle county, for most or all of that distance, would pass over this deposit, lying almost or immediately under the Drift deposits. A line from Oregon City to the same point, or lines from interme- diate points on Eock river to the same point, would pass over form- ations almost identical. From the uplift on Eock river to that on the Illinois river, there is probably a low axis of elevation some- where in the section of country bounded by the above imaginary lines. I have no doubt but that a broad strip of Lee county, extending from Grand DeTour to the northwest corner of LaSalle county,- is underlaid by the St. Peters sandstone. About Franklin, and even south of that, this strip may be covered with fragmentary patches and fields of overlying Silurian formations ; but artesian wells for all this distance would soon strike the St. Peters sand- stone, after passing through the overlying drift. The next visible outcrops of this formation in Lee county may be seen on Franklin creek. Several of these may be noticed, com- mencing about two miles below the village of Franklin, and showing themselves in the base of the creek bluffs all the way down to Eock river. The outcrops are low, and are sometimes capped by Buff and Trenton limestones. LEE COUNTY. 129 These are the natural outcrops of the St. Peters sandstone in Lee county. Along the northern line of the county, and east of Frank- lin creek for a few miles, other low-lying outcrops may exist. If so, I did not notice them, and they possess no peculiar interest. This sandstone has often been described. Its varying shades of <>olor, from white to dirty brown, rusty, and almost flame-red, are well known to all observers in its vicinity. Its want of cohesion, saccharoid, almost crumbling appearance, would seem to indicate that atmospheric and chemical agencies, such as the rain, the winds, the frost, and the tooth of time, would speedily level its piled-up sands and strew them far and wide; but this is contra- dicted by its remarkable property to weather into sugar-loaf shaped' hills, ragged pinnacles, apd gracefully rounded bluffs, able to pre- serve their form and shape through the rolling years. Where unstained by the oxide of iron, the grains of which it is made up are round and limpid in color, and are a pure quartz. The mystery of its deposition does not seem to be well understood. No fossils, no lines of stratification, have written on it and in it the story of its creation. Horizontal bands or layers, thin and dark iron- colored, weather out on some of the outcrops, and give the same a pictured appearance, at a little distance. On the point of one hill a pile of these fragments lay, detached from the outcrop, resembling a pile of old, broken, iron pots. On some of these fer- ruginous fragments I noticed the ripple marks spoken of by Dr. Everett, of Dixon, in his description of this rock. These ripple and eddy marks sometimes resemble the forms of organic life in a remarkable degree. Its uses will be spoken of under the head of the Economical Geo- logy of the county. Ascending the scale, we next come to the lower division of the Trenton. The Buff Limestone. Where in situ and fully developed, this lime- stone is separated from the St. Peters sandstone by two or three feet of thin shales, intermingled with a blue and greenish laminated clay. This is especially observable in one or two of the Pine creek outcrops in Ogle county. The best outcrop perhaps in Lee county is in a ravine two or three miles east of Dixon, near the Oregon road. The outcrop is about half way down a hill sloping to the south. In the bottom of the ravine some large detached masses of the St. Peters sandstone are laying in the bed of the little trickling stream. The top of this formation is probably just below them. The buff outcrop above and in the hill-side, formerly quarried largely, 9 130 ECONOMICAL GEOLOGY OF ILLINOIS. shows a compact, heavy-bedded, crystalline or semi-crystalline lime- stone. The massive layers are about a foot in thickness, and sep- arated by thin fossiliferous shales and loose clay. These layers belong to the upper part of the division. The lower part, as ex- amined in situ in Ogle county, is of a dull color, and gives out a dull earthy sound on being struck with the hammer, while these layers ring out a sharper and more metallic sound. Up Franklin creek in one or two places I detected the Buff limestone above and in close proximity to the underlying sandstone. These are all the outcrops noticed in the county. This Buff limestone underlies but a limited area, and that in close proximity to the sandstone out- crops. The base of the bluffs, from the Blue limestone quarries above Dixon to the sandstone bluff opposite Grand De Tour, contain good sections of this rock; but the outcrops are deeply covered by the talus along the bluff line. The Blue Limestone, or Trenton proper. This is very heavily devel- oped, both on Eock river and Franklin creek. About three miles and a half above Dixon, high, perpendicular outcrops begin to appear along the bluffs on the south side of the river; and from thence almost to the city limits of that city the bluffs are mostly composed of this rock. Extensive quarries and lime-kilns are seen at many places in this distance. The greatest thickness developed along these quarries is from sixty to seventy-five feet. The small ravines leading down through the hill, show this rock in their channels, sometimes, for several miles. In these localities it resembles the white Hamilton limestone about Eock Island. North of Eock river its area is more circumscribed. Following up Franklin creek this rock soon shows itself in the hill-side, even before the St. Peters sandstone has disappeared below the surface. In one instance a detached sort of a tower rock stands in the valley of the small stream, entirely disconnected with the hills on either side. All the way up the rocky exposures may be seen. Near the village* of Frank- lin, where the Dixon air line division of the Northwestern railroad crosses that stream, a series of large quarries, extensively worked in past years, line both sides of the creek banks for a considerable distance. A large hotel and other buildings in the village were con- structed with the material taken from these quarries. Franklin grove, a fair size body of timber, is underlaid by these beds, which outcrop in the creek. A section of Franklin creek would show the overlying Drift clays of varied thickness ; about forty feet of this Blue limestone ; and about twenty-five feet of the St. Peters sand- stone. These localities, and a few others in this part of the county,. LEE COUNTY. 181 are the only places in the county where natural outcrops of the Blue or lower Trenton may be seen. In the south and southwestern part of the county this rock may exist to a limited extent, but there are no natural outcrops, and it is hard to tell what formations lay under these level prairies. Where best developed in Lee county, the Trenton limestone at the top of the quarries is thin-bedded, broken up, and of a light- buff color. Towards the bottom the layers become heavier, intersected occasionally with upright clay seams ; and in the bottom several massive layers of blue stone are found. On fresh fractures the color is a dark-blue ; but it soon weathers to a bright sky-blue. Some of the layers are full of fossils, the remains of organic life. When highly polished, these make a handsome marble, covered with the delicate tracings of the embedded fossils and casts. In many instances I noticed the "pot-holes" spoken of by Dr. Everett, over the high surface of the country underlaid by this rock. They are a characteristic feature in the face of the country east of .Dixon, and excite the curiosity of the most superficial observer. The Galena Limestone. I prefer to retain this name in speaking of this member of the Trenton limestone. Descending Eock river from the locality of the Blue limestone quarries above Dixon, the Galena limestone is first noticed on the south side of the river,' in the fine outcrop just above the Dixon mills. The rock has been quarried here, making room for buildings and to obtain building material, until it presents a perpendicular wall of stone, perhaps forty feet high. The top of this outcrop is real Galena limestone; the middle has somewhat changed in character; the bottom pre- sents real beds of transition into .the underlaying blue beds of the Trenton proper. At Dement's quarry, one mile below this place, and on the north side of the river, and also in a hill at the north end of the Illinois Central railroad iron bridge, bold outcrops of massive, heavy-bedded, cream-colored and yellow Galena limestone are largely worked. Thence down the river on the north side for about six miles, to Lawrence's quarry, almost every hill shows a Galena outcrop. Dement's quarry, and a bold stone bluff, projecting over the edge of the river current, about three miles below Dixon, each expose a thickness of nearly seventy-five feet of solid stone escarpment. In this distance there is one heavy exposure in the south bank of the river. At Lawrence's quarry the rock presents a sort of a meta- morphic appearance ; and some of the layers are covered with a white incrustation of carbonate of lime, resembling the frosting on a 132 ECONOMICAL GEOLOGY OF ILLINOIS. cake. From this last outcrop tbe banks of the river run low, and show no. more rocks until the west line of the county is passed. South of Rock river, along these Galena outcrops, the country spreads away in a dead level towards the Winnebago swamps. No rocky outcrops are seen, between this section of the river and the south line of the county; but this long parallellogram i* probably underlaid by deep-laying Galena limestone, and patches of Cincin- nati shales, which -are shingled over it along the west line of the county. North of Rock river the country rolls away in undulating prairie and sparsely wooded stretches, and is all, with the exception, per- haps, of a small corner below the mouth of Pine creek, underlaid by the Galena limestone. The physical features of the country show this at a glance. The Illinois Central railroad, in winding out of the low Rock river bluffs towards Woosung, makes several long but not deep cuts in the Galena limestone. Several wells in the township of Palmyra disclose it at their bottoms. Along the banks of a little prairie stream northwest of Sugar Grove, at a locality called the Big Springs, two or three excellent quarries are opened and extensively worked to supply, the surrounding farms with building stone. The outcrops of this formation south of Rock river are not numer- ous, but still a considerable area is underlaid by it. Commencing at Mount Carroll, in Carroll county, a low,- anticlinal axis of the Galena limestone may be traced southeast through Milledgeville and Wilson's Mill to Rock river, just west of Dixon ; thence on the same general course to Lee Center ; thence bending south and west towards and near Sublette, and on to Lamoille in Bureau county. At Lee Center, in a grove of timber southeast of the village, there is a good exposure, where abundance of fine building stone is quar- ried. The stone is somewhat thin-bedded here. At Sublette, or its vicinity, there is another quarried exposure, and in northeastern Bureau county, if I mistake not, some low outcrops exist. The Galena limestone also comes in from Ogle county in the northeast corner of Lee, and underlies two or three townships there, extending down perhaps to the head waters of Spring creek and the Inlet marshes. It is almost impossible to trace or bound the underlying rocky formations in the level prairies of central and southern Lee county ; but \ feel quite sure the Galena limestone extends back for a considerable distance on either side of the anticlinal axis above referred to, and so continues until it runs under the coal fields of Bureau county, or thins out and disappears from among the under- lying rocks. LEE COUNTY. 133 An extended lithological description of this rock is hardly neces- sary in this place. It has been many times described in the reports of our Western geologists, and also in my reports upon Carroll, Stephenson and other counties in the northwestern part of the State. As developed in Lee county it is more massive and solid than in some localities further north, belonging as it does to the lower part of the formation. It has that rich, warm, cream-color so charac- teristic of this stone. The many economical uses to which this rock is put : its great thickness and local development, being only found in the lead basin of the Northwest ; the rich stores of galena contained in its crevices and resulting clays, and the geological questions and phenomena suggested by an examination into its deposition and the origin of its metallic wealth, will always make it a very interesting member in the series of Illinois rocks. Neither is it devoid of organic re- mains, as will be seen when I come to notice the fossils characteristic of these Lee county formations. The casts of fossils therein en- tombed are of more than usual interest. The Cincinnati Group. No regular outcrops of this formation, I think, exist in the county. I have intimated, in speaking of the Galena limestone, that nearly all that part of the county north and west of Eock river is underlaid by that formation. This is not fully correct. Linn Grove, near Eock river, and almost on the western line of the county, and a small strip of land surrounding it, has a thin deposit of the peculiar shales and clays of this group underlying the superficial deposits and overlying the Galena rocks. The mate- rials excavated from wells in that vicinity show this. In one other locality north of Eock river I suspect the existence of this formation. The base of "The Mounds," about two miles north and a little west of the west end of Sugar Grove, is composed, I think, of the shales and clays of this formation. There are no outcrops around these elevated and beautifully rounded hills. The gentle slopes leading up to their summits cover such outcrops with a talus, which has slowly accumulated around their bases. South of Eock river a narrow strip of the Cincinnati group comes into the county a few miles south of its northeast corner, but soon thins out and disappears over the underlying Galena. In the west- ern part of the county, about and running south of the station of Nelson, on the railroad, fragmentary patches and a limited extent of that part of the county is likewise underlaid by the Cincinnati group. 134 ECONOMICAL GEOLOGY OF ILLINOIS. The local extent of this formation being small, and there being no outcrops to attract attention, I do not deem it necessary to dwell further upon it. These are all the formations developed upon Eock river in this county. In reviewing what I have said about them, it will be very evident that the geological position of Dixon, and the rocks devel- oped in the short distance between Grand De Tour and the west line of the county, are of quite an interesting character. Geologists always spend the time occupied in their examination with interest and pleasure. The Niagara Limestone. "The Mounds," referred to above in speaking of the Cincinnati group, are capped, I think, "with a light- bedded, broken-up Niagara limestone. The outcrop, however, rather suggests than shows this formation. All this portion of the country once undoubtedly was covered by the Niagara limestone underlaid by the Cincinnati shales and rocks. But these have been removed by denudation, leaving these mounds as conspicuous landmarks, standing upon the underlying, level Galena limestone. This is the only Niagara outcrop, such as it is, that I detected in the county. I suspect that a considerable area in the eastern part of the county is underlaid by this formation. A strip six or eight miles wide comes in from De Kalb county, about the middle of the eastern end, and extends westward nearly to the low land of the Inlet swamp, where it thins out and disappears. The only evi- dence of this is the existence of Niagara rocks in De Kalb county, in such a position as to favor this supposition. The general topo- graphy of the face of the country also makes this look probable. The formation is not of sufficient importance in Lee county, either on account of its economical uses, its extent, or its geological interest, to call for a more extended description. Fossil Remains. Three of the above formations the Buff, the Trenton, or Blue, and the Galena are characterized by an abund- ance of fossil remains, in a very fine state of preservation. The characteristic fossils of the Galena limestone is the Recepta- culites Oiveni, or old Coscinopora sulcata, of the earlier geologists. In the common speech of the people it is known by various names, such as "lead fossil," "honey-comb," and "sunflower coral." A good specimen, with its central depression and folding-over edges, resem- bles the latter flower very much. In addition to this, of* which good specimens have been found around Dixon, other casts of character- istic fossils are numerous, such as Lingula quadrata; Murchisonia bellacincta; M. gracilis; fragments of Orthoceras; Ainbonyckia inter- LEE COUNTY. 135 media; Receptaculites globularis, rare,- Chtetetes petropolitanus, very rare in this rock; Calymene senaria, rare; Orthoceras anellum, a species of Cypricardites, rather abundant; Murchisonia bicincta; Illcenus taunts, rare; Raphistoma lenticularis, common; Bellerophon platystoma, com- mon; Ophileta Oweni, common; Illanus crassicanda, fragments and shields common,- Trochonema umbilicata, common,- specimens of Orthis, Ormoceras, and Maclurea, rather common,- a large species of Colum- naria, rather rare,- a species of Petraia? very abundant; and some other less common fossils, whose names I do not now recall. In the Blue or Trenton, of the old Western geologists, fossils are so abundant that it would be tedious to enumerate them. In some of the thin, shaly, blue slabs found above Dixon, fragments of corals and stems of Encrinites, Triiobites, Leptaena, Strophomena, Orthis, and other shells and fragments are embedded and stuck over them as close as they can be packed. A species of Orthoceras, sometimes attaining from six to eight inches in diameter, and from eight to ten feet long, is often found. Sections and fragments of this huge animal are of very frequent occurrence. A large chambered shell, probably the Lituites undatus of Hall, is very characteristic. Ormo- ceras tenuifilum; Gonioceras anceps; Orthis testudinaria; O. occidentalis; Stroplwmena alternata; S. filitexta; Leptcena sericea; a new fossil named the Vanuxemia Dixonensis, by Meek and Worthen ; and many others, too numerous to mention, are found in the outcrops along Rock river, in Lee county. The Trenton seas must have swarmed with these lower orders of life. In the lower earthy and sandy layers of the Buff limestone I have not noticed many fossils. The Buff limestone, of Kockton, in Win- nebago county, and of Winslow, in Stephenson county, is full of fossil remains of species and genera almost identical with those found in the Trenton quarries at Dixon. The thick layers of the outcrop east of Dixon are separated by thin layers, an inch or two in thickness, abounding with fossils and impressions. The species here are not numerous, but the individuals are clustered together in multitudes. They are mostly casts of shells in a poor state of preservation. The Lituites undatus, and the large Orthoceras, spoken of as found in the Trenton, are also characteristic of the Buff lime- stone. The Silurian fauna, disclosed in the geological horizon represented by these Dixon formations, was truly wonderful. The soft mud of these Silurian seas became the sarcophagi of extinct species and generations. We tread reverently among these old stones, marked with forms of life now fossilized ; for a great chapter of the history 136 ECONOMICAL GEOLOGY OF ILLINOIS. of the earth of the story of creation lies half revealed before us. The entombed relics of millions of years cycles in which man had no part Sibyline mysteries, almost too great for the finite mind to grasp the story of undefinable epochs, written by the infinite finger of the Creator, in strong traces these and kindred thoughts come over us, when gathering the fossils. No wonder Shakspeare could find "sermons in stones." The stones are full of sermons ; full of an inspired revelation ; they are the great Bible of Creation the Stone Book, whose solid leaves are pictured over with sublime truths. Surface Geology. The surface geology of Lee county is also interesting. The Drift beds or gravel banks the boulders or lost rocks the clays and the sand the alluvial deposits of the river and the swamps these form instructive chapters in a subsequent ancient history of the county. Alluvial Deposits. Eock river spreads out into a bottom land of limited extent, below Grand DeTour. This bottom land is composed partly of the Black river alluvium characteristic of river bottoms generally, and partly of banks and ridges of river sand ; but before reaching Dixon the rocky bluffs on either side have drawn close to- the river's shore, and for several miles below Dixon no alluvial de- posits exist, except the shifting sand bars and gravel beds in the stream. Before leaving the county, the bottom again spreads out, and occasional small flat expanses are covered by crumbling, marly sands and clays more recent than the true Drift. Even the exten- sive gravel beds worked by the railroad company, just below Nelson Depot, are river gravel beds belonging to this division of the Quater- nary system. The common prairie soil covering the county, composed largely of humus and the vegetable mold left by the successive growths and decays of the prairie grasses, of course belongs to these recent de- posits and is found all over the county. But the most marked of the recent deposits to be found in the county are the swampy lands of the Green river bottoms. The struggle between water and land over these affords one of the finest illustrations of the ftrigin and formation of the prairies to be met with in this part of the State. The land can almost be seen slowly encroaching upon the miry waters, and a real prairie taking the place of a water-logged swamp. A large part of the township of Viola, and parts of the townships of Eeynolds, Bradford and Lee Center, are taken up by the Inlet or Upper Green river swamps. This body of low land is about ten miles LEE COUNTY. 137 long, and from two to five miles wide. It is mostly covered with a dense prairie grass, among whose roots is concealed, in the wet seasons of the year, a thin sheet of water. Towards its center the water is deeper, and patches of cat-tails and rushes abound. On the south, the country slopes up gradually to the water-shed between this stream and Bureau creek ; on the north, to the dividing ridge between Green and Rock rivers. The southern slope is sandy prairie ; the northern is a rich, productive one. The soil in the swamp is a black, miry muck, carpeted with a prairie sod strong enough to bear the fowler's tread. The dryer portions of these swamps afford unlim- ited quantities of coarse prairie hay, much used in wintering stock. They also afford grazing for large droves of cattle in the summer season. The Winnebago swamps are even larger than the Inlet swamps, and have about them several new features. Hills of almost indurated sand rise in chains and clusters and groups from the midst of some of the swamps. These sand mounds and sand dunes were originally heaped up by the winds from materials brought from neighboring sand ridges, or at least partially formed in this way. Some of them are forty or fifty feet high, and are covered with scattering but stunted trees. The sloughs and swamps wind through them in many places, dark bands of green vegetation and glancing patches of water amid sand deserts and oak barrens. The intervening swamps are fringed with a band of thick-growing swamp grass, on a miry, mucky soil ; then comes an inner fringe of dense, cane-like rushes and cat- tails, growing so thick and tall that it is almost impossible to pene- trate it ; then come stretches of clear water, with hard, sand bottoms, over which one can wade easily without miring. No habitations are near these watery jungles. A spirit of desolation seems to brood over them. The tall, purple-caned reeds bend their light feathery tops in the wind ; triangular-shaped rushes cut the bare legs of the wader with their sickle edges. Innumerable water fowls congregate here in the spring and fall months, and the evening and morning hours wit- ness a babel of bird voices, nowhere else to be heard to an equal extent in the State ; and when the adventurous duck-hunter discharges his gun, the roar of myriads of wings, and an uprising cloud of the whole web-footed tribe, disclose 'tb^e fact that even these desolate spots have their uses. Of course this description of the Winnebago swamps applies to only a part of them. The rest are similar to the Inlet swamps, being more grassy and less wild. Some of these statements may not seem like the utterances of practical science. They are true, nevertheless. 138 ECONOMICAL GEOLOGY OF ILLINOIS. I have spoken of them at some length, because they are very marked features in the surface geology of part of this and the adjoining counties, and are known as remarkable places over all this part of the State. The Drift Proper. This county is covered with the usual drift clays of this part of the State. If these superficial deposits were stripped off, the surface of the underlying rocky formations would probably present quite as level an appearance as the present face of the county. The depth of these drift clays is hard to ascertain, being quite variable. Over the township of Palmyra wells are put down from thirty to fifty feet before striking the rock. One of these wells gave the following section, as given to me by the person who dug it : Feet. 1. Black mold and subsoil 6 2. Finely comminuted buff-yellow clay 12 3. Blue, compact, laminated clay 10 4. Black, oozy, marly mud, full of sticks, etc 5 At this point an abundance of rather brackish and not very sweet and pure water was struck, and the well up to the present time is never failing, and the water growing sweeter and purer. At other localities in this township wells are put down to the rock, and then drilled fifty or sixty feet in the Galena formation below, before water is found. Over the southern part of the county the drift clays are probably thicker than in the vicinity of Bock river. Where thickest, the blue clay is usually much the heaviest deposit, and is often underlaid by the black mud of the above section, No. 5, or by a bed of gravel and dirt of variable thickness. In the eastern and central portions of the county beds of sand often cover the surface and alternate with the clays below the surface. This blue clay and the black deposit containing the decayed re- mains of timber, and the gravel beds on which the blue clay often rests, lies at and near the base of the true Drift in this part of the State. Clay deposits covered the Silurian rocks before the Drift forces acted. These deposits were then undoubtedly very much thinner than now, and were derived from the slow decomposition of the underlaying rocks and partook of their characters. The ice and waters of the Drift period, the transporting, grinding and abraiding agencies then acting with so much power, increased these deposits very greatly ; mingled them up ; assorted them, and left them in their present forms as beds of sand, different colored clays, gravel and bowlder beds, and other deposits as we now find them, modified somewhat by subsequent surface influences. Since the Drift epoch LEE COUNTY. 139 there has been a constant struggle, with varying results, between the ravines and the level lands. Eains and water currents con- stantly struggle to cut out ravines in the crumbling clays. Eains and other atmospheric agencies constantly struggle to fill up these ravines, and i-educe the surface of the ground to a water level. These forces, thus acting in antagonism, nearly balance each other in their effects, and keep the general face of the country about the same. No extensive gravel beds of the Drift period were noticed in Lee county. Occasional nuggets of copper and galena are picked up in the surface clays and ravines. Scattering boulders are also often noticed in the ravines about Bock river and lying on the surface of the prairies even in the region of the swampy land. One remark- able flame-colored boulder, of several tons weight, lies on the side of the road a few miles southeast of Dixon ; another, of still deeper color, lies two or three miles east of Dixon. Either of them would attract the attention of the most casual observer, and he would find himself wondering as to their history and origin. 'Economical Geology. Building Stone. Plenty of good building stone is quarried in the outcrops of Trenton and Galena limestone along Eock river. These supply the country for some distance away from the river. The Galena quarry at Big Springs is extensively worked ; so is the one directly southeast of Lee Center. In the vicinity of Franklin the Trenton outcrop along the creek of the same name has been exten- sively worked, and the materials thus obtained used over the sur- rounding country and in the village for building and farm purposes. The sandstones of the St. Peters formation in some of the outcrops of Franklin creek are hard enough to be handled and hewn into shape, and are used to some extent for ordinary mason work. An old culvert bridge, one mile west of Franklin, is built out of this rock. In Ogle county, just across the line from Lee, we noticed one or two houses built of this material. But the rock is hardly hard enough to be handled well, and makes poor stone work. The Trenton limestone, for rough, ordinary mason work, furnishes a good material. It is very lasting, but very difficult to make hand- some work out of. The large mills at Dixon are mostly built out of this limestone; so are the buildings for some large manufacturing establishments located at Dixon. The stone is so easily quarried and so readily obtained, that it has added much to the building facilities of the city of Dixon. 140 ECONOMICAL GEOLOGY OF ILLINOIS. The Galena limestone, for heavy masonry, such as culverts, piers and the like, is the best in the county. The city of Dixon is now engaged (1868) in constructing a splendid iron bridge across Rock river to unite its north and south divisions. Two heavy abutments and a number of high, solid, and heavy piers were necessary to sup- port the great weight of iron in the structure, and to resist the crushing weight of ice which sometimes impinges against them in the spring floods. After an unsuccessful attempt to contract for Joliet or Athens limestone, the persons having the work in charge made arrangements to build the heavy work necessary to be constructed out of the layers of massive Galena near the city. To this end ,Dement's quarry, about a mile northwest of the bridge, has been heavily worked during the past summer. Massive stones have been quarried in great quantities and dressed into proper shape. The result is highly satisfactory. It would be hard to find mason work anywhere which, for warmth and softness of color, massive strength, and the quality to season harder as the work grows older, can excel that now being completed for the iron bridge at Dixon. ' Not only does this stone answer well for marine masonry, but for building private residences, whether dressed or bush-hammered, it is all that could be desired. For foundations, wells, and the many other uses for which a stone is required, it also answers well. Lime. Both the Trenton and Galena limestone burn into an ex- cellent article of common lime. The kilns below Dixon, along the Trenton outcrops, some years ago seemed to prefer this latter lime- stone. At that time and now they turned out a good article of this very necessary material. But at the present time the quarry near the mills in Dixon seems to be preferred, and a large kiln here is in constant operation. The top of the quarry is mostly used at the present time. The quarrymen take up the stone nearly on a level with the top of the kiln. This is a compact limestone, and makes both a strong and a white lime. The lower layers, the harder, sub- crystalline layers between the Galena in the top and the Trenton in the bottom of the quarry, a sort of transition rock between the two, are equally good for the same purpose. Great quantities of lime can here be easily manufactured. It might be produced for the home market and for shipment, and ought to become a source of material wealth, and one of the elements of the city's prosperity. Coal, lime, and clay for brick and pottery-ware, are great resources for the production of wealth and the enlargement of human happiness. LEE COUNTY. 141 Common Clays and Sands. These exist in abundance in every part of the county. From them a good article of common red brick and mortar for building purposes may be obtained. Fine gravel exists in the bed and banks of -Bock river, and can easily be obtained in any quantity desired for economical purposes. Other Deposits. The softer and whiter limpid quartz sands obtained from the St. Peters sandstone would furnish a good glass sand, and will be in demand some day for such uses. The subcrystalline strata of the Buff limestone would probably burn into a fair hydraulic lime, and, if so, would add materially to the resources of the county. Plenty of muck beds and half formed peat deposits of mud exist in the sloughs and swamps. These might be made valuable as fer- tilizers and amendments to the soil; but in the present state of prairie agriculture they are not in demand for this purpose. Good beds of peat ought to, and do probably exist in the swamps ; but none fit to work have attracted attention, so far as I know. Nuggets of copper are found in the drift clays, but are rather mat- ters of curiosity than of economical value. Pieces of galena have been found in the rocks in the northwestern part of the county ; but no valuable deposits of this metal probably exist in the Galena rocks of Lee county. The agricultural and horticultural resources of the county are about the same as those of the surrounding counties, and have been fully described in the reports upon some of these counties. CHAPTER IX. WHITESIDE COUNTY. The geology and physical geography of Whiteside county are of a most interesting character. The county is bounded on the north by Carroll county, on the east by Lee county, except the northeast corner, which is touched by Ogle county, on the south by parts of Bureau and McHenry counties, and on the west by Eock Island county, the Mississippi river, and the Marais d'Ogee slough. It is twenty-four miles long from north to south, and about thirty-two miles wide from east to west. It contains sixteen full townships, and four parts of townships on the western side. The number of square miles or sections of land embraced in all these is about six hundred and seventy-six. The surface of the county is greatly diversified. The northern, northeastern, eastern, central and southeastern parts are chiefly com- posed of high, level, rich prairie land, as well adapted for agricultural purposes as any of our Northwestern prairie lands. That part south of Eock river, except a strip. west of Prophetstown ; that part along the Marais d'Ogee slough on the west and southwest; the region of the Cat-tail slough, opening above into the broad Mississippi bottom, and below into the Eock creek bottoms these parts are level, low, and characterized by marshy, swampy, grass-covered sloughs and boggy and broad expanses of wet lands. In some of the western townships sand prairies of hungry, poor soil exist. The same may also be seen along portions of Eock* river. Along the western bluffs, and through the township of Ustick, the surface is rough and covered with oak barrens. An alluvial band of heavy timber fringes the lower part of Eock river. The high prairies are diversified with a number of beautiful groves. Among these, Genesee Grove, Union Grove, Eound Grove and Kingsley's WHITESIDE COUNTY. 143 Grove are the most conspicuous. Rock creek, Elkhorn creek and Buffalo creek have more or less timber, thinly scattered along their devious windings. The county, however, is rather scantily supplied with timber. The principal streams are Rock river, Otter, Rock, Elkhorn, Buf- falo and Sugar creeks, and some few smaller tributaries of these. Rock river enters the county at the center of its eastern boundary line, and takes its exit in its southwestern corner. Its general course is straight, its deviations crooked and many ; its current is broad and swift-flowing; its banks are high, except in a few places where alluvial bottoms spread out. Otter creek comes in from Carroll county and soon almost loses itself in the swamps of Willow Island lake, a few miles above Fulton City. Rock creek comes into the county about the center of its northern boundary line, flows in long undulating curves almost southwest, and enters Rock river at Erie. Elkhorn creek comes in near the northeastern corner, runs in the same general course, and enters Rock river at Como, a few miles below Sterling. Buffalo and Sugar creeks are tributaries to Elkhorn, coming in on the east side. Rock creek has three or four good water-powers in operation. The mills at Sterling are driven by one of the heaviest powers in the State. On Elkhorn creek two or three mills are in operation. On Buffalo creek one mill has been running since the days of the first settlements in that part of the State. Many other seats for fine water-powers exist on all these streams. Rock river, at many localities in the county, would furnish water-powers almost as heavy as the one at Sterling. At these localities the stream always flows over a floor of solid rock^. By constructing coffer-dams and partially turning the river out of its channel while the work is going on, materials for the most enduring dams may be quarried at the places where needed. It will thus be seen that, altogether, Whiteside county is rather sparsely timbered. It is well watered and well supplied with water- powers ; has abundant agricultural and manufacturing resources ; has a diversified surface ; and I am now to describe its interesting and varied geological formations. Geological Formations. These consist of Quaternary deposits of more than usual interest ; unproductive Carboniferous rocks of the true coal horizon ; sand- stones belonging to the Conglomerates, or "Millstone grits," lying at 144 ECONOMICAL GEOLOGY OF ILLINOIS. the base of the true Coal Measures ; heavy developments of the Niagara limestone ; widely extended outcrops or the Cincinnati rocks and shales, and considerable exposures of the Lead rocks of Galena limestone. Building them into a vertical section, the examined out- crops measure about as follows : Sections of Whiteside County Rocks. The usual Quaternary deposits from 10 to 80 feet Carboniferous rocks, shales, etc from 10 to 40 Conglomerate sandstone from 12 to 25 Niagara limestone from 24 to 175 Cincinnati group from 10 to 37 Galena limestone from 15 to 30 In most of these outcrops the maximum thickness at some places in the formation was reached. This was not true, however, of the Galena limestone. That deposit runs low, and its outcrops suscept- ible of measurement are much below its full thickness. I shall describe these formations in the descending order, commencing at the top. The Quaternary System. All the divisions of this system are recog- nized in this county. One of them, at least, is now attracting the attention of the capitalists and scientific men in a marked degree. I allude to the Cat-tail peat beds, the heaviest and best deposit of peat perhaps in the State or in the Northwest. Alluvium. An alluvial bottom extends along the Mississippi river, from Savanna, in Carroll county, to a few miles below Fulton City, in Whiteside county. It is from four to seven miles wide. It is naturally divided into two parts, nearly equal in extent. There is the high table lands ''not subject to overflow by the spring floods of the river, consisting of sand prairies, sand-banks, and occasional tracts of the richest alluvial farm lands. The other half is that low, wet, marshy bottom next to the river, and a chain of sloughs and marshes along the bluffs, subject to overflow at every period of high water. Upon it grows an enormous yearly crop of sedges and grasses, and the heavy alluvial timber belt of the Mississippi river. The sand-beds are finely stratified and contain occasional boulders, and beds of well worn, unassorted gravel. In one of these gravel beds, recently worked by the Western Union Railroad Company, a mass of transported rock of several tons weight was unearthed. It lies at least four miles from the bluff on either side of the river. The sand-ridge in which it was embedded is evidently an old Mississippi sand-bar, of more recent deposition than the Drift proper. How the great boulder came there, is a mystery. Perhaps when the WHITESIDE COUNTY. 145 great river extended from the Illinois to the Iowa bluffs, and the vast fields of ice came floating down in the colder springs of a former geological epoch, some of them were freighted with bowlders, which, as the ice fields went to pieces, dropped to the sandy bottom of the river. The lower water-soaked bottoms sometimes approach in char- acter imperfect peat marshes. The black vegetable mold covering them is often many feet in thickness. It is comparatively free from sand, and when reclaimed from the water is rich and fat, but too cold and sour for general cultivation, until sweetened by tilling and drying. Below Fulton City and on almost to Albany, and from the Maredosia slough to Cordova the alluvium rises into a high, buff colored sand prairie, fertile enough to produce fair crops, except in hot dry seasons, when every green crop is parched and withers beneath the blaze of an August sun. These sand prairies are old Mississippi sand-bars, resting against the bluffs extending east from these two towns, and running north many miles. Near the north- east corner of Garden Plain, the low alluvial bottom strikes off towards the southeast ; leaves the Mississippi river altogether ; makes a junction with the alluvial bottom of Eock creek in the township of Trenton ; and thence extends itself to the alluvial bottom of Kock river near the village of Erie. It contracts to an average width of half a mile. Low, abrupt, oak-covered hills rise from its edges. This is the Cat-tail slough, so famous for its magnificent deposit of peat, of which more will be said in another p'art of this report, Three distinct river beds are easily recognized at the present time. First, there is its present bed, about one mile wide on an average ; second, the low wet alluvial above referred to, and now subject to periodic overflows. When the waters filled this, the river averaged two or three miles in width. Lastly, the river once flowed a broad stream from bluff to bluff, and averaged six or seven miles in width. Then a heavy body of water flowed lazily through the Cat-tail, but as the great stream went down, this branch of it ceased to flow, and in its water-soaked bed gradually grew a great thickness of the hest peat. The Marais d'Ogee or Maredosia slough, as it is usually called, or Dosia, as it is called in the common speech of the people, is another broad marsh, spreading out along the line between this and Eock Island county, and extending in a nearly north and south direction, connecting Eock river with the Mississippi. Cat-tail slough is similar to the Maredosia, runs nearly parellel to it, and is distant some five or six miles from it. When the Mississippi river is high, -10 146 ECONOMICAL GEOLOGY OF ILLINOIS. the water runs south through these sloughs into Eock river; when Eock river is high, the water runs the other way. The highest point between low-water mark in the two rivers along the Maredosia is thirteen feet; along the Cat-tail, it is twenty-six. These figurea are obtained from actual surveys made along the sloughs in winter. I am indebted to the courtesy of Mr. J. Abbott, an accomplished engineer and surveyor of Cordova, for this interesting information. There can be but little doubt that the Mississippi river itself once flowed through the Marais d'Ogee. The evidence seems conclusive to any one making an examination of these localities. The broad bottom, several miles in width, looks like the Mississippi bottom. Then the mouth of Eock river was a mile or two below Erie. The same broad bottom runs along Eock river from Erie to Eock Island. Eound this channel the distance to Eock Island is .twenty miles greater than along the present course of the river. If flowing round this way at the present time, this increased distance would give the usual fall of six inches to the mile; but along the present channel of the river from Albany to Eock Island the distance is twenty miles less, and the fall eighteen inches to the mile. Besides this the abrupt, rocky hills approach closer to either bank of the river as it now runs; and there is nothing about it between these two points, having any resemblance to the usual alluvial bottom now under consideration. For some cause the Father of Waters left its old channel and broke through the rocky hills, gaining twenty miles in distance and leaving the upper rapids as the result. But leaving this interesting question, I will refer to the other parts of the county, where the alluvium is prominent. In the south- eastern part of the county the townships of Montgomery, Hahna- man, Tampico, Hume and Prophetstowu, are largely made up of wet or swampy lands. Peaty marshes and sloughs intersect the level face of the country. The soil is deep, black, and water-soaked. The famous Green river Winnebago swamp extends across the town of Hahnaman in a somewhat diagonal direction. This swamp is a wilderness of reeds, sedges, and miry sloughs, in which countless thousands of wild geese, ducks, swans* and other aquatic birds, in proper seasons congregate and find an- almost Arctic isolation. At almost any of these localities the origin and formation of the prairies is well illustrated. The highland round the swamps, aided by a vast yearly decaying vegetation, is encroaching upon the marshes and building them up into dryer prairie land. But the county of Whiteside is reclaiming her swamp lands, by an efficient system of ditching, faster than Nature ever dreamed of doing. Thirteen miles WHITESIDE COUNTY. 147 of big ditch are now finished and under contract. Already, hundreds of acres of land, after being drained, have advanced in value from a few cents to many dollars per acre in value. The scheme promises to add greatly to the material wealth of the county. The usual dark surface, organic, geine soils of the prairies, the leaf molds of the groves, the sands and gravels recently deposited by Eock river, and the white soils of the barrens and oak timber tracks, may be said to make up the rest of the alluvial deposits. Loess. When the Mississippi occupied the higher of the three beds above referred to, and extended from its eastern to its western line of bluffs, and in many places spread out over the level prairies, the term river was hardly a proper designation for the great sheet of water. It approached more nearly the character of a great lake or inland sea of fresh water, with its surplus water falling over the mountain chain of its southern boundary, like some Niagara, pour- ing out the overflow of the great lakes of the North. This barrier over which the water rushed, crossed the river, like a great dam, where the "Devil's Bake-oven" is now pointed out to the traveler. As this was worn down and the bed of the Mississippi lowered, the water assumed more and more the form of a river, draining the great basin thus exposed. The action of the low running waves and other aqueous agencies threw up and arranged in part the bluffs around its shores, while the great basin was full of comparatively currentless water. This deposit is the Loess. It is composed of light -colored, finely comminuted clays, white and yellow sands and sandy marls, all generally partially stratified, and containing lacus- trine and fluviatile shells and other fossils. The Loess bluffs are generally bald knobs, covered with short tufts of grass. A good example of the Loess may be seen where the Northwestern railroad strikes the bluffs east of Fulton City. The bluffs here are made up nearly altogether of the Loess. South of this, along the Cat-tail, the bluffs are in part capped by the same deposit ; but in going north they soon rise into the rocky walls and high mural escarp- ments of the Niagara limestone. The low hill north and \est of Morrison is partly composed of Loess clays. Eock river and the smaller interior streams did not present favorable conditions for this deposit to take place, and we seldom find it away from the bluffs of the Mississippi river. Drift. There is a marked distinction between the Drift in this and counties farther east. The coarse gravel beds of its upper divi- sion are almost entirely wanting. The recent gravels of Eock river were the only real gravel deposits I observed. The usual blue-colored 148 ECONOMICAL GEOLOGY OF ILLINOIS. and yellow plastic clays of the lower Drift cover the underlying rocks in many places to a considerable thickness. At one locality a well was sunk twelve or fifteen feet through yellow unctious clay ; then blue clay was struck, and in about fifteen feet more a great quantity of sticks and wood, apparently cedar and pine, was found. The water in the well, of course, had a brackish taste. This woody dep'osit was about the base of the true Drift. Occasional bowlders are found in the ravines, but they are nowhere abundant. Over the northern parts of the county, and especially that portion underlaid by the Galena limestone, the reddish clays or hard-pan of the lead region exists to a considerable depth. These Drift clays, however, as developed in this county, have in them nothing of peculiar or marked interest, except that they bear evidences of peaceful forces rather than that tremendous power which strewed the bowlders and yield up the gravel beds in many places in the neighboring counties Whether the floating iceberg, or the slow-crawling glacier, or the strong water currents, or all these combined, transported the coarser materials of the Drift, the force of the powerful agents were much modified in their action here. In the spring of the year the -ice in Eock river sometimes, impelled by the strong current, gorges, until it rises to the height of fifteen or twenty feet, and then with a crack- ing roar it tears rocks from their beds and trees from its banks, grinds them in its strong jaws, and throws them high on the land or strews them along its bottom. But away from the river the clays of the Drift appear as if deposited and arranged in peaceful waters. The Carboniferous System. While making the examinations at Sterling, I was repeatedly told that coal had been found three or four miles below the town. The supposed outcrop was stated to be a thin seam in a bend of the river, not far from the edge of the water. The same statement is made, I think, in Dr. J. G. NORWOOD'S small report on the coal-fields of Illinois. I sought out the locality, examined the river, and made inquiries of an intelligent farmer, who has resided near the spot for many years. With him the existence of coal in the neighborhood was a faint tradition, nineteen or twenty years old. An examination of the river showed that its bed or floor consisted of the soft, white, dendrite-speckled upper division of the Niagara limestone. Gravelly banks of river drift rose on one side some twenty-five feet from the water's edge ; a low alluvial bottom lay between the river and the high prairie on the other. No sign of any outcropping rock exists, except in the bed of the river. This is the general character of Kock river from Sterling to about seven miles below Erie. No coal seam or outcrop of coal, in my judgment, WHITESJDE COUNTY. 149 exists at the point designated. Some one. digging along the banks of the stream at an early day, doubtless came upon a small deposit of float or drift coal. Tradition has kept the circumstance alive, and it grows with the passing years. The edge of the Coal Measures, however, extends thinly into Whiteside county, at its southwestern corner. Opposite Erie, the south bank of Rock river begins to assume the character of a low bluff-line. In descending the stream these, bluffs rise in altitude, become more abrupt and broken ; and such are their general char- acters until the Mississippi range of bluffs is reached, several miles below Rock Island. For most of the distance the glancing waters of Rock river hug their bases. On the north side of the stream the low alluvial bottom spreads out, widening in proportion as the range of hills rise in height. A hundred feet is perhaps the highest alti- tude attained by these bluffs. A short distance below the western line of the county, coal begins to outcrop in the sides of these bluffs. Still lower down, at Aldrich's coal mine, the seam is some four feet thick, and is extensively worked. Cannel coal, soapstone, fire-clay, black slate, and a stratum of black limestone are associated with the coal. The outcrop is in the side of the hill, at a considerable elevation above the waters of Rock river. Below this mine, and in close proximity to it, several Sterling capitalists own land, and have opened drifts into the hill. Still lower down, at Cleveland, coal is extensively mined ; and lower down, Coal Valley is pouring its black treasures into Rock Island, and from thence is distributing in every direction the old imprisoned heat and blaze of the Carboniferous ages, to warm our prairie homes through the bleak winters. My field- work, however, did not extend into these rich coal regions, and I refrain from further description of them. These coal bluffs extend for a few miles into Whiteside county. But no productive coal seam has yet been found in them, within its limits. The bluffs run too low, by the time the county line is reached, to indicate a workable coal vein. A thin seam and light outcrops may be discovered, but so far as the economical geology of this county is concerned, the Coal Measures may be set down as unproductive. No workable beds extend within its boundaries. The Unionville Sandstones. In the northern part of the township of Hopkins, 1 unexpectedly found a low outcrop of sandstone in a ravine. The stone was soft and friable ; in color it varied from a dirty- white to a clouded or yellowish-red ; it easily crumbled beneath a blow of the hammer, and could be cut or hewn readily with a common ax. It resembles the St. Peters sandstone, and at first 150 ECONOMICAL GEOLOGY OF ILLINOIS. surprised me not a little. Other outcrops, however, indicated its true geological horizon. The outcrop may be found on the land of a Mr. Johnson, on section 13, if I mistake not. A well, sunk higher up on the side of the ravine, or near its head, penetrated the sand- stone about thirty-three feet, when the bottom of the bed was prob- ably reached. This locality is about eight miles east and a little south of Morrison. A line drawn from Johnson's nearly west to Unionville, and thence southwest to Mineral Springs, in the south- western part of the county, would pass through six or seven locali- ties where this sandstone outcrops, or has been dug into. About three miles west of our first outcrop, and not far north of the vil- lage of Round Grove is the locality of the famous walled well of Whiteside county. Some ten years ago an article went the rounds of the papers, stating that in digging a well at this locality, after a depth of twenty-five feet was reached, the top of an old walled well was discovered, which showed unmistakably that it was the work of human hands. TJie old well was filled with debris. After removing this to a depth of several feet, sweet waters rose, until the wall of the old well was covered. The supposed discovery, at the time, excited general and even scientific interest. I sought out the old well, and tried to learn its history. It is now filled up. The porch of a farm house extends over it. Its wonderful story was freshly told to me, in the truth of which the narrator seemed to have full faith. Something like a walled well was, no doubt, actually discovered; but from all the light I could obtain on the subject, I think it was only a rounded excavation in the underlying sandstone a pot-hole, perhaps worn out by an eddy and moving pebbles revolving in a circular motion. In sandstone, with broken and thin-bedded strata, the inside of such an excavation would present exactly the appear- ance of an artificial well. And thus, this supposed wonder, like the walled lakes of Iowa, and other supposed works of art, is suscepti- ble of a simple and satisfactory explanation. To me the chief interest in the well .consisted in the fact that its walls were built of my newly-discovered sandstone, enabling me to trace the general course of its deposit. The next outcrop is in the grove about one mile east of Unionville. Here it is quarried to a considerable extent. But the most characteristic outcrop is at Unionville, one mile north of Morrison. Here a heavy quarry is largely worked. A section of this quarry shows about nine feet of light marly clay, resembling Loess, about three feet of alternating clays and soapstone, and WHITE SIDE COUNTY. 151 twelve feet of massive, heavy-bedded sandstone. Three strata or layers of the latter outcrop, each from two to three feet thick, sep- arated by layers of soapstone embedded in thin seams of clay. One of these soapstone layers is six inches thick. It is of a blue-white color, greasy and unctious to the touch and feel. The sandstone layers are soft, light-colored, finely-grained arenaceous rocks. They can be hewn into any shape with an old ax, but when seasoned and dried they harden into a fair building stone. The surface of some of the larger blocks is beautifully covered with very distinct ripple and wave marks. About seven miles southeast of Unionville, on the Poor farm, is another outcrop. It is in the face of the east bluff of the Cat-tail. This quarried outcrop is similar to the one just mentioned. The bluffs on both sides of the Cat-tail, in this vicinity, show signs of this sandstone. At Mineral Springs, on Kingsley's Grove, still -further to the southwest, the borings of a small artesian well showed it to be the underlying rock. This well was put down in oil-fever times. Some indications of oil still exist about these chalybeate springs ; but after prospecting awhile, the enterprise was abandoned. Following the same general course, we next find outcropping sand- stones in the Mississippi bluffs, near Hampton, in Eock Island county. The rock has a resemblance to the Unionville sandstones, but probably belongs to the true Coal Measures, a little higher in the geological scale. The sandstone deposit rests unconformably upon the Niagara limestone. At one time it was thicker, and covered a larger extent of the county, but the erosive and denuding forces of past geological ages have worn it down and carried it away, until nothing but. small patches and basins remain. Its place in the strata of Illinois rocks is at the base of the Coal Measures. It belongs, I think, to the. Conglomerate, which, in the West, is often only a. fine-grained, arenaceous rock; but in oiher localities is made up of coarse sandstones, pebbly conglomerates, and grits. Fossils. The Unionville quarry has afforded a considerable num- ber of impressions and casts of fossil plants. The most conspicuous among these is a Calamite, the Calamites cannceformis, I think. The casts of this plant are from one and a half to four inches in diam- eter, the joints from three to about eight inches in length, the sur- face finely marked with longitudinal lines. The friable nature of the rock makes it difficult to obtain specimens. A species of Lepi- 152 ECONOMICAL GEOLOGY OF ILLINOIS. dodendron has also left some well-clefiuecl impressions. It seems to have been as thick as a man's arm, and the impressions have a rough, shark-skin, rattlesnake-like appearance. I could not obtain a good specimen, and am unable to give it a specific name. Some other sections of what appeared to be a plant were observed ; but the impressions were too indefinite for identification. The Niagara Limestone. A large extent of this county is under- laid by this formation. Probably all that part of the county south of Eock river is underlaid by the Niagara, except a little strip along the Sterling dam, and the Carboniferous bluffs below Prophetstown. In all this extent of territory there is not an outcrop or quarry, however, of any kind, except those in and along the bank of Kock river. The surface is low, and the underlying rock runs low. The river, from Sterling to its exit out of the county, every few miles, runs over rocky beds of porous, dendrite-specked, yellow Niagara limestone. Just below the dam at Sterling, at Lyndon, at Erie,, seven miles below Erie, and at many other intermediate localities^ quarries are opened at the water's edge, or in the floor of the river ; and judging from the appearance of the low wet prairies south of the river, the Niagara runs back nearly level, perhaps, beyond the southern limits of the county, before running under the Bureau and Henry county Coal Measures. About a mile above Sterling, on the north bank of the river, a series of Niagara quarries are extensively worked. The formation here is worked down about thirty-five feet, and the rock is full of chert bands, and is speckled with dendrite markings. The layers, although thin-bedded, are so uncouth and rough that no mason could build them into a handsome wall. The bottom layers are of a dull green color, and soon pass into the underlying Cincinnati shales. Quarries of the Niagara are also worked near Empire and Como, one of .them in the bottom of a little tributary of Elkhorn creek. The outcrops here are low and not very heavy. Westward of these latter places and in all that tract of country bounded by the railroad track, Eock creek and Eock river there is scarcely an exposure of any kind ; but this irregular-shaped triangle is nearly all underlaid by the Niagara limestone. Eock creek, from the north line of the county to Morrison, and in fact to its mouth above Erie, cuts into the underlying rock and exposes it at numerous places. All these exposures belong to thia formation, except the sandstone at Unionville and Mineral Springs. At Brothwell's mill the exposure is sixty feet thick, presenting a WHITESIDE COUNTY. 153 perpendicular bluff, cavernous, and light-colored on a recent frac- ture. Just above Jacobs' mill an extensive quarry is opened in the same limestone. In the hill north of Morrison it is again quarried. At this latter place a lime kiln is in successful operation. Some of tbe layers here have in them many small, curiously shaped cavities, lined with a velvety-looking, lead-colored metallic substance. The bluffs along both banks of the Cat-tail, with the exception of a few sandstone outcrops, show the Niagara limestone. That high plateau of -land bounded by the Cat-tail, the Maredosia and the Mississippi, and consisting of the townships of Newton, Albany and Garden Plain, is underlaid by the same rock. At Albany a high rocky hill, with an old shore line of the Mississippi, fifty feet above present low-water mark, rises a short distance back from the river. The hill north of Fulton City, and on which it is partly built, is an outcrop of Niagara limestone. At one time it was a small rocky island in the midst of a broader and mightier stream than the present Mississippi river. But the grandest development of this formation, perhaps, in this part of the State, may be seen along the Mississippi bluffs, near the north line of the county. After viewing these beetling cliffs, the appropriateness of the old name, "Cliff Limestone," becomes appar- ent. This bold exposure rises at its highest altitude to the heighth of one hundred and seventy-five feet above the level of the bluff road, and this -is but the upper portion of the formation at this place. The talus and debris of ages have accumulated along the base, rising in slopes half-way up the steep aclivity. Loose stones, sometimes weighing tons, loosened by the frosts and other atmospheric agencies, have rolled down, and thickly strew the roadside. Sweet, sparkling, deliciously cool water gushes in strong springs from little ravines. Wild grape vines, dense thickets and old monarch oaks cover these talus slopes for the most part ; but sometimes the scene is varied by a slope covered with short tufts of prairie grass, or the richer and softer blue grass. The upper part of the exposure resembles dilapidated Cyclopean walls of the mystic times. A long mural escarpment rises from the top of the slopes, and presents its castellated face to the broad Mississippi Valley, whose lacustrine waves in older geologic epochs beat against the rocky barrier and wore it into fantastic shapes. Many caverns exist, some of them almost inaccessible, out of which issued, the day 1 spent among them, the half human cries of wild-cats and the growls of a small species of lynx. Some miles of stone wall along 154 ECONOMICAL GEOLOGY OF ILLINOIS. the road are built, by quarrying the material on the tops and sides of these steep rocks, and letting it go plunging down to the very places where it is needed. The little farms thus fenced along the public highway have a fat, rich, sour, cold soil, too wet for very successful cultivation, except in occasional mellow localities. As we recede from this bluff line towards the interior of the county, the Niag- ara limestones thin out by erosive and denuding agencies, until the Cincinnati shales and the Galena limerock successively come to the surface. This is especially true along the northern part of the county, where the exposure is so much the heaviest. In the large area of Whiteside county underlaid by this portion of the upper Silurian rocks, I noticed considerable difference in litho- logical character. The exposure just referred to consists of the upper "Coralline and Pentamerus beds" of the Cliff or Mound limestone of the earlier western geologists. It is compact, homogeneous in struc- ture, full of minute specks of dendrites, of a light straw color on a recent fracture, sometimes taking a reddish tinge, nearly the color of brickdust. At Sterling the lower part of the formation is exposed. This is a thinner-bedded, rougher, uglier stone, and would hardly be recognized as the same rock just referred to. At Fulton City the upper part of the quarry, at least, is a friable yellow-colored or ochreous limestone, sometimes porous or sponge-like, and sometimes of a tough crystalline texture. Sometimes the color approaches an almost white cream-color. It is identical with the Racine limestone of Mr. Lapham, referred to in the Wisconsin geological survey. At Lyndon the rock is porous and full of the stems of encrinites. Below Erie, near the point where Eock river leaves the county, the color is still lighter and more delicate, the texture more compact and finer- grained, and the stone is in every respect, I think, identical with the LeClaire limestone, now recognized as a member of the Niagara formation. Organic Remains. The characteristic fossil of the upper beds, per- haps, is the Pentamerus oblongus. In the speech of the people, masses of it are commonly called "petrified hickory-nuts." At Brothwell's mill many of them are sticking through the rocks ; but at the heavy exposure along the bluffs huge stones are covered over so thickly with the casts that they seem to be an aggregated mass solidified with a calcareo-magnesian cement. In the old Niagara seas they must have grown in countless millions, like oysters in a modern oyster bed. Some of these vast slabs would make attractive specimens for the geologist's yard ; but good cabinet specimens are hard to obtain. Along the Niagara ridges, and in the ravines, casts of corals turned WHITESIDE COUNTY. 155 to silex may be picked up in great quantities. Among the most common is the well known chain coral, the Halysites catenularia. Favosites Gothlandica. F. favosa, F. Niagarensis, Stromatopora concen- trica, S. rugosa, Astrocerium venustum, one or two species of CyatJio- phyllum, .stems of Encrinites, and fragments of Orthoceras of at least two species, are all very abundant. From the abundance of these silicified corals, coral reefs must have existed in the old Niagara seas, where countless millions of these little animals lived and built, as the modern coral-builders raise up, from the modern ocean's floor, reefs, atols and islands. In these clear coral-growing seas, sea weeds or fucoids abounded, and in the Sterling quarries are woven over some of the layers in a perfect net-work. Cincinnati Shales. The rocks of this formation, formerly desig- nated as the Hudson Kiver shales, but now known as the Cincinnati group, show surface exposures over a considerable portion of the county. Along the rapids at Sterling, on the banks of the river and at the base of the bluffs under the Niagara quarries already referred to, the various rocks, shales and clayey and bituminous deposits of this formation may be seen. The rapids in the river are to some extent produced by the wearing away of these deposits. They rise at a considerable angle from beneath the Niagara rocks just below the dam. On the south side of the river the formation can hardly be distinguished, but on the north side, a mile above town, it attains a thickness of thirty-seven feet, from the surface of the water to the base of the Niagara limestone. From thence it runs round east and north of Sterling, three or four miles distant from the city, striking off into the large Cincinnati surface exposures in the neighborhood of Dr. Pennington's residence. In this circular belt there are no surface exposures after leaving Bock river, but the wells dug indicate the existence of these shales and shaly limestones. The inevitable blue clay and creamy- colored water, oozing from some small ravines above Sterling, are unfailing indications of this deposit, even where no outcrop is visible. That high plateau of level prairie between Elkhorn and Bock creeks, and extending from the railroad track to a mile within the limits of Carroll county, except a small portion of the southwest corner, is underlaid by the rocks of this group. This elevated water shed contains large portions of four or five townships. Bound its eastern and northern edges, and. in many ravines inside of its bound- ary lines, good exposures and artificial outcrops may be examined. Bock creek cuts into the Niagara, and Elkhorn creek cuts into the 156 ECONOMICAL GEOLOGY OF ILLINOIS. Galena limestone, but the Cincinnati rooks and shales run over the one and come from under the other, in less than one mile from either stream. Along its northern limits it rises to the altitude of almost a hill, overlooking the low-lying Galena deposits of Carroll county. Three or four quarries are opened along the face of this elevation. The average thickness of these exposures is about twenty feet. The stone is thin-bedded, easily broken, close in texture and light in color, having a dry or baked appearance. The bottom layers are thicker-bedded, and have a faint green or blue tinge. It is an argillaceous shaly limestone. At Bressler's mill, on the east side of the ridge, there is a low outcrop just above the water's edge. Here the rocks are stained by iron-impregnated waters, flowing from some springs just above them. Nearly a mile northwest of this is Dr. L. S. Pennington's large quarry, opened at a considerable distance from and elevation above Elkhorn creek. The exposure is stripped of the overlying clay and worked into about thirty feet. A drain is con- structed to lead off the water. The upper portion of the quarry is thin-bedded, but the layers can be lifted in immense slabs. No better flagging-stone can be obtained anywhere. The lower portions of the quarry are thicker-bedded, compact, and very blue. On section three, in the town of Hopkins, there is another splendid quarry of this stone. The part worked is about twelve feet thick. It is cov- ered by a few feet of finely-comminuted light-colored clay. A circu- lar pool of sweet, clear, cold water, fed by some large springs, lies in placid tranquillity almost in the quarry, and throws off a laughing stream. The stone here is a hard, thicker-bedded, compact, argil- laceous limestone, unlike the usual crumbling shales of the Cincinnati group. Two or three of the bottom layers are of a deep ultra- marine blue color, with shaly and clayey partings of a few inches thickness between them. The locality is known as Hecker's quarry. It is now owned by Dr. Pennington. There is another quarried exposure nearly a mile north of this, at Harvey's. The stones here are soft, shaly and crumbling. The tooth of time makes sad havoc with them. When exposed to the atmosphere they soon begin to decay. Here I noticed some disturbances in this usually quiet formation. Over a few sections it seems to be thrown out of shape. Not far off some Niagara rocks are found where they do not belong, accord- ing to outcrops and the signs in the surrounding hills. These lost Niagara rocks are evidently not in situ, but have been moved prob- ably by the drift forces. WHITESIDE COUNTY. 157 The lithological character of the Cincinnati rocks examined in this county deserves a passing thought. The carbonaceous and bitu- minous shales found further north, which are there a very marked feature, are here almost entirely wanting, or are at least not dis- tinguishable by ordinary observation. The stone is compacter, and less liable to decay, than that examined in many other localities. It approaches nearer an ordinary limestone in structure and in uses. And altogether it is a valuable deposit, as I shall show in speaking of the economic geology of the county. Organic Remains. These are not very abundant. Most, of the heavily worked outcrops are barren of fossils. In the ravines cutting the formation on the north the Chcetetes petropolitanus, Orthis testu- dinaria, 0. occidentalis, O. lynx, and a small Brachiopod, probably a Leptcena, are often picked up, weathered out in great perfection. The spines and shields of a characteristic trilobite, the Asaphus gigas, are not rare, but perfect specimens are seldom found. At Sterling some of the thin layers are exceedingly hard, almost flinty, and are thickly covered with fossils. Conspicuous among these is the Strophomena alter nata, and among other shells common to this and the Trenton period. The Galena Limestone. This becomes the surface rock to some ex- tent along the northern and northeastern part of the county. That irregularly shaped parallelogram in the latter locality, north of Sugar creek and east of Elkhorn creek, is all underlaid by the Galena limestone. Buffalo creek cuts this piece of land in a diagonal shape. For two or three miles west of Polo this creek runs over and shows exposures of the Blue limestone ; but at Sanfordsville, near the line between this and Ogle county, this rock outcrops heavily just below the dam for the saw mill. The outcrop has been worked to the depth of twenty-four feet. The layers are massive, solid, and subcrystalline. At the present time the quarry is not much worked. Following the creek down a few miles, the next ex- posure of consequence is at Wilson's mill. Here there is a quarry worked to the depth of about twenty feet. The stone is similar to that at Sanfordsville. Other small outcrops may be seen in this locality in some small ravines in a white oak grove of some extent. On Elkhorn creek, at Allison's mill, just across the line in Car- roll county, there is a worked exposure some eighteen or twenty feet thick. The stone here is of a white cream color, and quite handsome in appearance. From this locality nearly to Bressler's mill, just east of the residence of Dr. Pennington, the Galena is 158 ECONOMICAL GEOLOGY OF ILLINOIS. the surface rock. It runs low, however, and soon disappears below the overlying Cincinnati group. The central part of that broad stretch of prairie and rough land north of Morrison, and lying between the Mississippi bluffs and Hock creek, is also underlaid by this rock. There is no conspicuous outcrop anywhere over it; but some of the ravines, especially near the Carroll county line, show its peculiar gravels, red hard-pan, and low-lying, crumbling outcrops. There is nothing noteworthy connected with this limestone as a surface rock in this county. Its superficial area is limited, its out- crops are few, and the only scientific interest attached to it is the knowledge of its existence among the other interesting formations of the county, and the fact that it may become of economical interest for the manufacture of quick-lime. It is almost barren of fossils. I only noticed fragments of a few characteristic species. Near the northern part of the county I found a rather poor specimen of Receptaculites and fragments. of Bellerophon, Plcurotomaria, and Murchisonia. Economical and Agricultural Geology. This department of Whiteside county geology is of more than usual importance, both in a scientific and economical point of view. The variety of rocks ; the new interest awakened in the cultivation of the vine ; rich and varied agricultural resources ; the great beds of excellent peat existing in hitherto useless bogs, and the fat lands now being successfully reclaimed from the swamps all these are matters of wider interest than usually appertains to a single county. Building Stone and Lime. All the outcropping formations above described furnish materials for ordinary mason work, such as cellar and well walls, foundations, and public buildings. The Galena re- quires much labor to quarry and work it into good shape ; but it lasts like granite, has an attractive, warm, fashionable cream or straw color, and for heavy massive masonry has no superior. Its limited outcrop prevents is general use for economical purposes. It burns into a good article of quick-lime. There is a lime-kiln in successful operation at Wilson's mill. While at Sterling I observed some capitalists, who were intending to manufacture a quantity of lime, figuring whether they could haul stone to the fuel or fuel to the stone the cheapest, the one being in Sterling and the other on Buffalo creek. I did not learn the result. WHITESIDE COUNTY. 159 For common rough mason work the Niagara limestone is much used. Some of its layers make a good quick-lime, as may be seen on the ridge north of Morrison. The sandstones 'of Unionville and the county farm are also ex- tensively used for building purposes. The mill between Unionville and Morrison is built of this soft gray stone. It is a handsome and substantial structure. The jail and court house foundations, and the public offices in Morrison belonging to the county, are of the same material. When first quarried it is so soft that it can be hewn into any shape with an old ax. It then appears unfit for building into any structure. But when laid up in a wall it dries, seasons, and attains a firm texture. The ease with which it can be worked recommends it, where dressed stone is desirable. In some places the shales and rocks of the Cincinnati group are considered unfit for permanent mason work. It is supposed that atmospheric agencies will eventually destroy their beauty and injure their durability. But so far as tested, the quarries of the Cincin- nati group in this county furnish a lasting and desirable material for economic uses. The layers are of convenient thickness, and break into any desired size. The flag stones raised at Dr. Penning- ton's home quarry are as large as need be wished for. This gentle- man, with his accustomed energy and a large expenditure of money, has two large quarries in operation. He has also a stone yard in Sterling, where he can furnish stone from his quarries in any quan- tity, and dressed into any desired shape. He supplies this stone yard from the quarry near his residence, and from the Hecker quarry in the township of Hopkins, already referred to in this report. A handsomer^ looking lot of stone than those quarried and corded up at the latter locality last fall, one seldom ever sees. I hope merited success will crown Dr. Pennington's efforts to develop this branch of the material wealth and industry of the county. As pertinent to this part of our subject, I here insert a table showing the tests and properties of many samples of stone. Some of them are from the quarries of the Cincinnati group just referred to. Others are from the Niagara limestone from different localities in Northern Illinois. The table is given entire, on account of the interesting nature of its contents, and as furnishing a basis of com- parison between our Northern Illinois and some other rocks. It was furnished to myself and Dr. Pennington by the government officials on Rock Island. I regretted that no specimens of the Galena limestone were present to be subjected to the same trying ordeal. It will be seen from the table that the samples of stone 160 ECONOMICAL GEOLOGY OF ILLINOIS. from Dr. Pennington's Cincinnati quarries were in many respects superior to the LeClaire limestone, out of which the United States Arsenal at Bock Island is built, and were almost equal to the Joliet marble, out of which the United States Armory is being constructed : Table showing Properties of Stone. Kinds of Stone. Dimensions in Inches. No. Samples . . Specific gravity Crushing force, in Its Crushing force, inlfrs, persq're inch Began to spawl Breaking w'ght for transverse strain Transverse strength *L W 2. S-4 b d Athens marble (Illinois Stone Co.), Magnesian limestone. Athens marble (Walker), Magnesian limestone. Joliet (State Prison) Mag- .iesian limestone. Magnesian limestone. Nauvoo, Pure limestone. Blue stone (New York), or North river flag- stone. Le Claire (Old Quarry) Magnesian limestone, very impure. Le Claire (New Quarry) Magnesian limestone. Andalusia Magnesian limestone (very im- pure). Transverse, 3.75X7.9X20 3.9X7.05X20 4X8X20 Crushing, 2X2X4 Transverse, 4X7.5X20 4X8X20 3.8X8X20 Crushing, 2X2X4 Transverse, 4X8X20 4X8X20 4X8X20 Crushing, 2X2X4 Transverse, 4X8X20 4X8X20 4X8X20 Crushing. 2X2X4 Transverse, 4X8X20 4X8X20 4X8X20 Crushing, 2X2X4 Transverse, 30X4X3 30X4X4 30X4X5 30X4X6 Crushing. 2X2X4 Transverse, 4X8X20 4X8X20 Crushing. 2X2X4 Transverse. 4X8X20 4X8X20 Crushing, 2X2X4 Transverse. 3.8X7.95X20 3.7X8X20 4X8X20 Crushing. 2X2X4 1 2 3 2.5154 2.5132 65, 700:16, 420 65, 700 16, 900 49, 000 16, 255 49, 000 18, 580 64,800:16,700 64,000!16,600 =361.5 =377.4 =324 1 2 3 2.514360,500 t 2.662934,500 2.527143,700 2.524633,000 15,12559,56717,360 8,62528,00012,100 10,95039,000,16,800 9,50038,000,14,300 =354.3 =172 =328 =294 1 2 3 2.4051 2.6123 2.6086 38, 733 40, 000 31, 270 33, 000 9,69235,000 10,00020,000 7,817 18,000 8, 150 19, 000 14,400 13, 800 15,000 18,800 =264.5 =269 =293 =267 1 2 3 1.6105 2.6526 2.6354 34,757 64, 000 47,000 65,500 8,656 16,000 11,750 16,375 19, 000 64, 000 44, 000 65, 000 15,867 15,309 16, 400 =276.5 =298.7 =220.3 =248 i 14,708 7,850 9, 150 8,950 57,833 2.6440 2.6378 2 .7028 58, 883 31,400 'M. 200 35,000 15,850 14, 600 14, '00 14, 600 =283 i=285 =273 =285 1 2 3 4 2.6703 2.7249 2.7242 34,200 84,600 95,300 89, 500 8,583 21,150 23, 825 22, 375 14.300 4,000 5,680 8.890 10,000 =281 =623 =665 =616.75 =520.8 1 2 2.7245 2.3354 2.3379 89, 800 13, 000 13,800 20.0(10 22,450 3, 250 4,700 5, 000 7,142 6,590 6,890 =609 =127.7 =130.5 11,000 18,800 20.000 2 2.336615,600 2.371224,900 2.303329,800 121,500 4,31716,600 6,22524,900 7, 450 25, 000 5,375 15.000 6,695 7,000 9, 100 =129.6 =136.6 =177 1 2 3 2 337225,400 2.3790:24,200 2.4(1(1? 28, 100 2.381220,000 21,633 6,350 6,050 7,025 5,000 8, 050=156. S 5,900=112 5, 000 =105 3, 600 =103 4,833 2.338924,100 6,025 =107 *NOTE. The product of the length and width divided by 4 times the breadth and depth gives the transverse strength. tDefective. WHITESIDE COUNTY. 161 Table showing Properties of Stone Continued. Kinds of Stone. Dimensions tn Inches. No. samples,.... Specific gravity Crushing force, in fts Crushing force, infts.persq're inch Began to spawl Breaking w'ght for transverse strain Transverse strength L W 2. 8-4 & d Sterling, 111. (Penning- ton), Magnesian lime- stone. Hopkins, 111. (Penning- ton). Wills Quarry, Hancock, Illinois. Wills Quarry, Hancock, Illinois (Magnesian limestone). Bickey's Quarry, Lee Co., Iowa (Sandstone). Crushing, 2X2X4 from top 2X2X4 from bot. Crushing, 2X2X4 Crushing, 2X2X4 from top 2X2X4 from bot. Crushing, 2X2X4 27,540 6,885 5,250 40, dOO 34,000 10,000 8,500 3,250 6,000 2.468 32,100 8,025 25,000 2.387 16,000 4,150 9,000 2 180 15, 700 3,925 15,700 To determine the absorptive properties of different stones, the fol- lowing varieties of different stone were placed in the boiler of a steam engine, and remained for sixteen (16) days. They were then weighed, and then placed in water, where they remained three (3) days and nights, and were again weighed, with the following results : Kinds of Stone. No. of specimens Weight before steeping Grains. Weight after steeping Grains. Increase in weight. Grains. Increase per cent. Athens (Illinois Stone Company) 1 2 1 2 3 1 2 1 2 1 2 1 2 1 2 1 J 1 2 1 5554 5421 5020 5140 5230 5293.5 5306.3 6211.8 6640.5 5498 5578.7 5635 4479 4999 7 4333 4611 4902 4798 4425 4020 5755.5 5593.5 5184 5309 5300 5495.3 5432.5 6382 5800 5513.5 5599.5 5661.5 5498.5 5361.2 4674 4874 5181 4924 4701 4230 201.5 172.5 164 169 171 101.8 126.2 170.2 159.5 15.5 20.8 26 5 19.5 361.5 341 263 279 126 276 201 3.6 3.1 3.26 3.28 3.26 1.8 2.3 2.73 2.8 .33 .39 .47 .45 7.23 7.8 5.7 5.68 2.5 6 5 Athens (Walker) 4 > t Jol et (State Prison) : Jol et (Sanger) Nauvoo Blue stone, New York LeClaire, new quarry old quarry Andalusia Wills quarry, from top from bottom Rickey's quarry 11 162 ECONOMICAL GEOLOGY OF ILLINOIS. The soils, clays and sands have been sufficiently referred to in speaking of the surface geology of the county. They furnish the usual materials for economical purposes and uses, and need not now be more specifically referred to. Vine Culture. The cultivation of the vine in some parts of the county is awakening deserved attention. The experiment, so far as tried, has been eminently successful. Several amateur grape-growers in the city of Sterling are devoting some attention to this interest- ing branch of industry. Their success has been most flattering, and there is a well-grounded belief springing up that both grape-growing and wine-making, in favorable localities in Northern Illinois, may be made a source of profit to the cultivator. The soil in and about Sterling seems well adapted to vine-growing, At Morrison, the soil partakes somewhat cf the nature of the Loess clays. The vine flourishes in it in the greatest luxuriance. I observed, last fall, one little vineyard just below the town, on a southern slope of the hill, which seemed, from the highway, nothing but a mass of purple grapes. I have since been furnished with some statements as to the amount of fruit raised, mode of culture, and other facts of interest to vine-growers. The vineyard belongs to Canfield Blodgett, Esq. He has 140 bear- ing vines, of which 90 are Concords, 24 Hartford Prolific, 6 Dela- wares, 6 Crevelings, 6 Taylor White or Bullitt, 6 Maxitawna, and 2 Cuyahoga. The vines were planted three years ago last spring, on soil heavily manured and subsoiled. The crop of 1867 was as fol- lows : 3,018 pounds, sold at an average of 16 cents per pound ; about 500 pounds were used by the family and friends of Mr. Blodgett; 20 gallons of wine, the pure juice or blood of the grape, were made ; layers were sold to the amount of $100 ; layers yet on hand, about $40 worth ; net profits on 140 vines, three and a half years after planting, on a single crop, at least $500. He has since planted 320 vines, not yet in bearing, varieties as follows : 115 Con- cord, 50 lowas, 40 Israelas, 50 Delawares, 13 Adirondacks, 13 Ives' Seedling, 13 Clintons, and 26 Hartford Prolifics. The ground for these was trenched two feet deep, and a load of well-rotted manure to every five vines, well mixed with the earth. He takes down and trims in the fall, and covers with earth, and takes up about the middle of May. It takes ten or twelve pounds of grapes to make a gallon of wine pure juice and two pounds of sugar. Where one- third water is used it takes more sugar, and the wine is of inferior quality. WHITESIDE COUNTY. 163 The above statement can be relied on, I think, as correct. It shows what may be accomplished on a small scale. It is true, vines would not bear every year as they did in 1867, but they would produce with as much certainty as our most staple products of the farm. The Loess hills along the Mississippi, with their marly clays and sands, may be made to do even better than this. Proper care in planting, and a generous after-culture, would produce this delicious fruit and a generous, invigorating wine in the greatest profusion. Grape-growing and wine-making in this country is rapidly rising to a prominent position among industrial pursuits. In California, it is now the leading interest of the State, surpassing in importance the production of gold. In a few years it will, even now perhaps it does, surpass all other interests combined. Our California wines are be- coming as familiar as the products of the vintages of the Old World. Cincinnati wines establish the fact that the Ohio valley is eminently well adapted to vine-culture. The hills of the Missouri river are attracting to them the wine-making Germans from the best vine lands of the Ehine, and of other famous wine-producing countries. The Loess bluffs of the Mississippi, about Warsaw, Nauvoo, Fort Madison, and in that locality, are surprising horticulturists by the adaptability of their soil and climate for the growth of the vine and its abundant yield of grapes. In this latter locality, the Catawba is the favorite wine-grape. It has stood the test of a severe trial, and the wine-growers have faith in it. In Whiteside, Carroll, and coun- ties farther north, the Concord is the favorite grape. It is found to be hardy, prolific, reasonably sure of a crop, and comparatively free from mildew and insect foes. All over the district where the Galena and Niagara limestones outcrop, the deep, loose, red soil, intermixed with loose stones, ought to, and will produce grapes that will make a wine of high excellence and great durability, although it may not attain the richness and ripeness of flavor of that grown in sunnier climates. In the latitude of Nebraska, the Concord, Hartford Pro- lific, Taylor's Bullitt, Ives' and Norton's Virginia, and Clinton, have all, after a thorough test, proved successful. Some of them never show mildew, or a diseased berry, and are not subject to the ravages of insects. If we could produce grapes for the table and for wine, even as abundantly as we produce apples for the cellar and for cider, how much would be added to our material wealth, our social enjoyment, and the healthfulness of our people. A new and profitable industrial interest would spring into existence ; a blow would be struck at the 164 ECONOMICAL GEOLOGY OF ILLINOIS. consumption of poisoned and adulterated liquors ; and a pure, healthful and invigorating beverage would be furnished, which would do much for the destruction of a perverted taste for alcoholic stimu- lants. I have a deep and abiding faith, that the awakening interest of our people in the cultivation of the vine, and the making of wine, will do much towards the accomplishment of this result. Peat. In Whiteside county peat exists in inexhaustible quantities and of first rate quality. It has become not only a subject of wide- spread scientific interest, but an element of material wealth, and one of the industrial and economical resources of the county. The most valuable deposit is found in the Cat-tail slough, a low swale running through the highlands from the Mississippi to the Eock Kiver bottoms, in the western part of the county. In width this slough varries from one-half to three-fourths of a mile. From Bluff station to Eock creek, the Cat-tail proper is about ten miles long. A heavy vegetation of sphagnous mosses, sedge grasses, cat- tail rushes, and other aquatic plants cover it. In approaching it from either side over the rolling prairie, .no indications of its exist- ence are discovered, until the low bluffs running along either side are reached. The broad, water-soaked swale then opens upon the sight, gray at the touch of October frosts, except where blackened by the sweeping march of recent prairie fires ; dotted with haystacks ; a creeping stream of antiseptic peat water, shining like a thread of silver in the shallow black ditch, opened to drain the surplus waters of the bog thus it appeared when I first went there to pursue my investigations of the peat-beds of the county. Much and various qualities of young, growing and unripe peat exists all along the slough. But the great bed of fat, ripe peat, which has made the name of Whiteside county peat prominent in connection with the peat deposits of the Northwest, lies near the middle of the Cat-tail, and not far from the water-shed or dividing ridge between Eock and the Mississippi rivers. Mr. Nathaniel Dodge, who resides in the vicinity, about twelve years ago had his atten- tion attracted to the valuable character of this peat deposit. At first it was cut into convenient sized blocks with a common spade, and dried in the summer sun. Neighboring farmers began to use it for fuel and heating purposes. It was used for burning lime from the Niagara limestone, in the adjoining bluffs. It was hauled to Mor- rison in small quantities and burned in offices and dwellings. At length, stimulated by the experiments and successes of Eastern peat companies, and the reported examinations of geologists and practi- cal men, a peat fever sprung up in Whiteside county, a steam WHITESIDE COUNTY. 165 engine was placed in the swamp, and two peat machines were ope- rated by Messrs. Townsend & Dodge, during the summer of 1867. Three hundred tons of dry, hard peat fuel were manufactured. The experiment was a success. The manufactured fuel became popular and valuable. Peat lands, hitherto considered almost a drug in the market, rapidly increased in value, doubling and quadrupling in a few months. The Union Grove Peat Manufacturing Company, of Whiteside county, with a cash capital of one hundred thousand dol- lars, has just been organized, and its articles of association filed with the Secretary of State. During the summer of 1863 extensive works will be put in operation, and large quantities of peat fuel manufactured. ' The bed of peat is in all about six miles long, averaging in width about three-fourths of a mile. It contains, altogether, some three thousand acres of peat lands. These land do not all contain valu- able workable peat, but the greater part of them do. The amount of peat contained in such a deposit is almost beyond belief. It is considered a reasonable estimate that one acre of drained peat will produce two hundred and fifty tons of dry fuel for every foot in depth. If the Cat-tail would average ten feet thick of work- able peat, and this estimate is perhaps below the truth, then an acre would furnish twenty-five hundred tons of dry fuel. The blocks made last summer were almost as dense as bituminous coal, and readily sold for seven dollars per ton or cord. Five dollars could be realized for all that can be manufactured. The price of manufac- turing the fuel need not, I think, exceed two dollars and fifty cents per ton. This leaves a net profit of over six thousand dollars to every acre of ten foot peat. At these figures a hundred acres of this best peat land would be worth, as an element to convert into material wealth, over six hundred thousand dollars. Some geologists reckon a ton of well manufactured peat fuel as equal to a cord of dry hickory wood. If this is true, the Cat-tail is indeed a valuable deposit. I sat by a peat fire several frosty even- ings, while making my investigations in this part of the county. The fuel certainly made a cheerful fire. It was burnt in a grate; made little smoke ; left little ash, and that light and white ; there was no unpleasant smell, and a bright flame was given out. It consumed, however, rather rapidly, and as a generator of heat is not equal to the better varieties of coal, or the harder varieties of dry wood. And yet, after all this apparent fair showing, some caution ought to be exercised in the investment of money in this new enterprise. 166 ECONOMICAL GEOLOGY OF ILLINOIS. The great labor of handling the raw material must ever make the cost of manufacturing peat bricks a considerable item of expense. The Rock Island coal-fields are at no great distance, and for many years will cheaply furnish a good article of Illinois coal. The cost of peat machines is quite an item, and experience may encounter unexpected difficulties as further progress is made in the work. I simply throw this out as a doubt in my well-grounded faith in the final and complete success of manufacturing crude peat into a cheap and valuable fuel. For coking purposes, and for the working of iron and steel, it is said to furnish a heating material more valuable than any now in use. The principle of manufacturing the fuel, now being applied in the Cat-tail mills, is essentially that of Weber. The crude peat is ground by cutting arms, revolving in a strong box, between fixed arms. When the texture or fiber is destroyed, it is molded into con- venient sized blocks ; some of the water is squeezed out ; it is then dried a few days or weeks in the sun, and eventually is cribbed like Indian corn in covered narrow plank cribs. Condensation is chiefly effected by a destruction of the fibrous texture, permitting the peat, when it dries, to contract into a more solid form. Com- pressed peat, or peat made by an attempt to press or squeeze the water out, no matter how powerfully the pressure is applied, will not succeed in making the pressed material either dry or solid. Good peat is very elastic. When the pressure is removed it returns to nearly its original volume. The partial closeness of texture given to the outside hinders the drying process. Actual experiments have taught the manufacturers this truth, and they have abandoned the idea of pressing the water out by mechanical means. A cord of wet peat, by the natural process of drying, shrinks to one-third or one-fourth its original size. Condensed into the solidity of ordinary coal it shrinks much more. This loss of bulk and weight is caused by the evaporation or loss of the water contained in the peat. The great desideratum is to get rid of this large amount of water as economically and with as little handling as possible. New processes of manufacture, new applications of labor-saving machin- ery, and cautious but liberal outlays of capital, will yet overcome every difficulty now in the way ; and as the wants of the human family require new supplies of fuel, the bogs and marshes will fur- nish it, as the barren hills now spout forth their treasures of oil. The peat furnished by the Cat-tail deposit is of excellent quality. It contains few veins of sand, mud, or other impurities. When first dug the blocks have a dark, almost black color, and unctious WHITESIDE COUNTY. 167 or greasy feel. When dry it becomes comparatively light, has a fine, spongy, fibrous structure, and compares favorably with dry peat blocks from the heather-clad moors and heaths of Scotland or the Emerald Isle. The Sphagnum mosses are the true peat producers; but in our western sloughs, swales, marshes and bogs, grasses, sedges, and other species of aquatic vegetation, contribute largely in making up the beds. Grass peat, when old, thick, and subjected to pressure, makes a solid, lusterless, dark-colored peat ; moss peat, under the same circumstances, is a little more fibrous in texture; both growing together make a modified peat. In the Cat-tail and other similar sloughs the ground is covered with a short, thick, velvety moss, out of which rises a dense vegetation of grasses, sedges and rushes. The ground has a quaking tread; is saturated with water; and the heavy vegetation, as it settles down, becomes perfectly soaked and even covered with water. The mosses keep drying at the roots and growing at the tops. The antiseptic peat water arrests rapid decay. From this slow decay, by chemical action, solid compounds are formed able to resist decay. The mass grows, and a peat bed is the result. Pile a mountain upon this highly concentrated vegetable matter, sink it beneath the ocean's level, and cook it, or season it for a few millions of years, and a bed of coal would be the result. It will thus be seen that moisture and a low temperature are essential to furnish favorable conditions for the growth of peat. In the dry sandy soil of Winnebago county, for instance, little peat can be found ; in the swamps and marshes of Whiteside county it is found in all stages of growth and ripeness. The Cat-tail is a ripe, fat and old deposit. I will now pass to some of the younger and more unripe beds. In the Maredosia slough I heard of some peaty deposits, but did not examine them. They are probably not of much value as a fuel. Southwest of Prophetstown there is a peat marsh known as "The Big Slough," extending from near Bock river in a southeast direc- tion until it loses itself in the Winnebago swamps. Its average width is nearly half a mile. I spent a day boring in this great deposit with the peat augur. In thickness the peat is from four to nine feet. A foot or two of fibrous turf covers the top of the marsh. Alternating layers of a coarse, red, unripe peat, and veins of mud and sand and other earthy substances, were observed at every boring. Silver- shining threads and fibers show themselves in the good peat. They result from the partial decomposition of coarse, wirey grasses. The deposit, in several stages of its growth, seems 168 ECONOMICAL GEOLOGY OF ILLINOIS. to have been overflowed by water. At each flooding earthy matter and sand was swept over the slough and deposited as a sediment. At present a heavy growth of Sphagnous mosses is flourishing in the greatest profusion over the whole slough. This great slough, for the reason stated, is not so valuable for fuel making as the Cat-tail ; but for fertilizing purposes it is per- haps better. Many less valuable deposits of peat exist in the lowlands towards the Winnebago swamps; but I deem a minute description of them unnecessary at this time. I cannot leave this swampy region, how- ever, without noticing a curiaus phenomenon often seen among them. I refer to the sand-hills, sand-dunes, sand-blows, or "blow- outs," as they are called in the common speech of the people. The wind has built the sand into curious-shaped, ever-changing hills. The "blow-out," about twelve miles south of Sterling, is a circular range of low sand hills, inclosing a small lake. It looks like the extinct crater of some old volcano, but owes its peculiar shape simply to the action of prairie winds. The Sphagnous mosses and the highly concentrated cooked vege- table matter of these peat beds, in chemical composition, are similar to the woods of our forest trees. Where pure, ripe and fat, this peat can readily be converted into a cheap and valuable fuel valuable as a clean, healthful fuel ; valuable, on account of its strong flame and freedom from ash and clinker, as a steam generator and locomotive driver ; valuable, on account of its freedom from sulphur and other metallic impurities, for working iron and steel ; valuable, for its fine coke producing qualities, and the many other economic uses to which it can be put on account of its fine heating properties ; and cheap, because the supply of raw material out of which the fuel can be manufactured is inexhaustible. The youngest, unripe qualities may be put to use as a fertilizer and a valuable addition to the poorer prairie and hill soils. For this use it is almost invaluable. Geine or humus is the fertile element in all soils. It is also the life of stable and barn-yard manures. This is so well understood in New England States, under the scientific investigations of their agricultural chemists and geolo- gists, that peat, and even the pond mucks and muds, are every year composted in large quantities, and spread over the thin soils, with the happiest results. Agricultural chemistry has demonstrated that the salts and geine of a cord of wet, raw peat are equal to the manure of one cow for three months. Practical agriculture has also demonstrated that WHITESIDE COUNTY. . 169 crude peat, in a raw state, is too acid and sour to be immediately beneficial to the soil. By composting for a few months with wood ashes, lime, potash, or common manure, the whole mass becomes sweetened, and one of the best and strongest fertilizers for farm crops is produced. The orchard, the vine and the garden fruits feed greedily upon this compound, and bear abundant crops. When necessity compels our prairie farmers to turn their attention to fertilizers, these unripe peat beds will become the most valuable spots on every farm. Tracts of sterile land in Maryland, worth but four or five dollars an acre, suddenly increased in value to forty dollars an acre, upon the discovery in their neighborhood of the wonderful fertilizer, the green marls of Maryland and New Jersey. A peat bed is not only valuable itself, but will eventually confer a new value upon all adjoining lands, if properly used. Clays, Sands and Soils. Further remarks upon the clays, sands and soils of this county, and their products, seem hardly necessary. The discussion upon these topics in the Ogle county report might be applied with nearly equal truth to this county. Antiquities. I cannot close this report without referring briefly to the antiqui- ties left by the mound builders. Near the Niagara limestone quarries above the city of Sterling, on a high table land overlooking Eock river from the north bank, is a large congregation of these mounds. Along the south bank of the river, below the city, many large ones are scattered along. Most of these Sterling mounds are the common round ones. Their size is a little larger than the aver- age. A few oblong ones were noticed, but none of the strange effigies and mystic representations observed at some other localities. Mounds also exist about Portland, and many other places along Rock river. Many of these mounds have been partially excavated, and some trinkets and pieces of charcoal taken therefrom. These are commonly believed to be burial mounds ; but there is reason to think that many of them are house mounds, or hut mounds, made by covering some sort of supporting structures with sods or surface earth, for winter residences of extinct races of men. The charcoal found in them would indicate the fires once 'kindled, perhaps, in the center of these low, earth-covered huts. The fact that these mounds are composed of surface soil, with no depression 170 ECONOMICAL GEOLOGY OF ILLINOIS. near them, indicates that the materials of which they are composed were gathered from the surface of the earth. Later generations have doubtless used these structures as places of interment for their dead. Whether used as human habitations, burial mounds, memorial or sacrificial monuments ; whether built by the Indian tribes, or races of men older than they, may remain a mooted question. The researches of antiquarians and archaeologists may yet throw a flobd of light upon these interesting investigations. The red man was doubtless a mound builder, but I think more primitive men than he built many of our mounds. In these structures he may have buried his dead, but older and higher civilizations than the red man built earth-works for defense, boundaries and national purposes long before the Indian roamed over these hunting grounds. The usual flint arrow-heads, stone axes, and other stone imple- ments, though not abundant, are sometimes picked up. One relic was found a few years ago, in the banks of the river at Sterling, which deserves more than a passing notice. The imple- ment is, I believe, of pure copper, fashioned into the form of a long, heavy knife. The broad end has a hole through it, and is turned over from the edges towards the center, making a place or socket for a wooden handle or spear-shaft. The blade is eleven inches long; it is nearly an inch and a half wide near the heel of the cutting side ; from thence it tapers on both sides to. a blunt point. It has a vein-like appearance over it, caused by the unequal decay and eating of the copper rust. It was found some seven feet below the surface of the earth, sticking out of an embankment which had caved into Kock river. The formation was a dark-colored diluvial, or river drift, made up of black or dark-colored deposits, containing chert and considerable river gravel. The spot where found is seven or eight feet above ordinary water-mark. If found where indicated, this relic is older than the historic period, and is in some way doubtless connected with the ancient mining of the Lake Superior copper mines. Prior to the wearing away of the Cincinnati shales, where the Sterling rapids are now located, the bed of the river was higher, and the rapids further down the stream. At that time the stream might have formed the embankment where this primitive knife or spear-head was found; but even that view of the case makes it almost of pre-Indian origin.* * NOTE. This knife has been figured in the Transactions of the Chicago Academy of Science, Vol. I, plate 23, fig. 3. A. H. W. WHITESIDE COUNTY. 171 The bone from the fore leg of the Mastodon found in Ogle county, and referred to in the report of that county, was found in the same river gravel or drift, and at the same depth below the surface. This fact seems to indicate that the Mastodon and the maker of this copper knife existed at the same time in the Eock Kiver valley. CHAPTER X. BUREAU COUNTY. This large county is located in one of the finest agricultural por- tions of the State. It is bounded on the north by Whiteside and Lee counties, on the east by LaSalle, on the south by the Illinois river, and parts of Putnam and Stark counties, and on the west by Henry county. The Illinois river also touches the southeastern boundary line for four or five miles, and the south side of the town- ship of Milo joins upon the north side of Marshall county. The county is longest from east to west, being six townships, or thirty- six miles. It is four townships, or twenty-four miles from north to south, except where the township of Milo extends south of what ought to be the southern line. There, of course, the distance is six miles more. The county thus contains about twenty-three and one- half townships, or eight hundred and forty-six square miles or sec- tions of land. The general configuration of the face of the county: its groves, streams, soil and other characteristics, are similar to those of Henry county, with the exception of some peculiarities along the Illinois river. The prairies are not quite so rolling as those of Henry county. The timber skirts the streams more in belts, and fewer groves stand like islands over the expanse of the prairies. The sur- face of the ground rises and falls in long, swelling undulations, separated in places by level stretches of country. The streams wind in long curves. The soil is light and warm. Corn and the grains, grasses, fruits, potatoes and the other staple products of Northern Illinois grow luxuriously, and are almost never failing. Streams. Greei river enters the county about twelve miles from its northwest corner, flows south with very crooked windings through the township of Greenfield; then turns westward through the north BUREAU COUNTY. 173 part of the township of Gold to the west county line, cutting off from this corner of the county the township of Fairfield and parts of the two townships just mentioned. Green river has here its usual characteristics. These three townships have in them large bodies of genuine Green river swamp lands. Big Bureau creek comes in from Lee county near the northeast corner of Bureau. It flows in a general southwest direction to a point a short distance west of the city of Princeton; from thence it takes a south course for ten or twelve miles, and then turns nearly due east and falls into the Illinois river some five miles from where the south boundary line of the county strikes that river. This stream has very little alluvial bottom land along its course. The prairie rises in rather abrupt swells from the banks of the stream. About Tiskilwa and on to the Illinois river there is an alluvial bottom, covered with a dense growth of timber. West of Little Bureau creek is a tributary of the former, rising in the northern part of the county and forming a junction with the larger stream a few miles southwest of Princeton. It is a smaller stream, but of the same general character. Brush creek and Coal creek are small prairie streams, the latter flowing near Sheffield, and losing itself in the Green river swamp land. On the southeast corner of the county, the Illinois river forms the boundary line for a distance of some fifteen or sixteen miles. There is a broad alluvial bottom along the river on the Bureau county side. The lowest bottom is mostly a swampy, grassy plain, interspersed with sloughs, and ridges of river sand, and subject to inundations when the Illinois river sends out its floods over the low banks. One of these sloughs assumes the character of a lake, communicating with the Illinois river at its southern terminus. The town of Tren- ton is built upon the west side of this lake, half a mile or more from its outlet into the river. At ordinary or high stages of water steamboats enter this lake slough, and make their regular landings at Trenton. I shall have more to say of this valley when describ- ing the geological formations of the county. Timber. Along Green river there are a few scattering bunches of rather scrubby timber. Big Bureau has a scattering belt along its margin for a considerable portion of its course above Princeton. Below that city it enters a timbered region. The townships of Princeton, Indian Town, Arispe, Lepertown, Selby, and Hall, in the south and east portions of the county, all have considerable tracts of timber. Those below Tiskilwa, and bordering the Illinois river, 174' ECONOMICAL GEOLOGY OF ILLINOIS. are bluffy, and mostly covered with a scattering growth of such trees and brush as may be found in similar localities in the north- ern part of the State. Big Bureau Grove, in the western part of the county, has a con- siderable body of timber. Crow Creek, in the township of Milo, and Pond creek, west of Tiskilwa, two small streams not named above, have each some scat- tering trees along their courses. "Dad Joe's Grove," in the northwestern part of the county, is a small grove on a very high elevation, and is a conspicuous land- mark for a long distance over the prairies. These groves and timber belts furnish a fair supply of timber, and add variety to the landscape. The rest of the county is prairie land, some of it level and some undulating and rolling. The two northern tier of townships, the western and southwestern townships, and the north parts of Hall, Princeton and Selby, are such prairie lands. The water sheds between these streams rise to a considerable height in places, but I had no means of ascertaining how high. The dip of these water sheds and the elevation of the different parts of the county above some given point, as for instance the waters of the Illinois river, would aid materially in fixing the true horizon of some of the coal seams to be spoken of hereafter. Geological Formations. No county in this part of the State presents so poor an oppor- tunity for the investigation of its geological formations. With the exception of the Illinois river bluffs from Trenton towards Peru, in LaSalle county, and a small ravine or two near Tiskilwa, there is hardly an outcrop of a single rocky formation in the county. The Chicago, Burlington and Quincy railroad traverses the entire county diagonally from the northwest to the southeast corner, a distance of about forty-five miles. With the exception of a few gravel beds and clay banks, its excavations present no sections of interest to the geological examiner. The Eock Island and Chicago railroad traverses the southern part of the county through its roughest portions, from the west to the east line, and the same may be said of it. Green river, in this county, has no sign of an outcrop in its low, swampy banks. Big Bureau, West Bureau, and their tributary brooks, with but a few exceptions, cut into no rocky formations. When the rail- roads and streams, which traverse and cut a county in all direc- BURKAU COUNTY. 175 tions, show no natural sections of the rocks, the difficulty of cor- rectly describing the underlying formations will at once be seen. The following section of the Bureau county rocks and Drift deposits is approximately correct. The reasons for giving it thus will appear in subsequent parts of this report : Ideal Section of Bureau County Formations. \. Quaternary deposits, such as Drift clays and gravels, Loess, and alluvial clays and sands 150 to 250feet t 2. Coal Measures, such as sandstones, shales, limestones, soapstone and hard clay 250 to 400 " 3. Cincinnati group of shales ? ? 4. Galena limestone ? ? .5. Trenton proper, or Blue limestone ? ? Commencing with the top, I will describe these formations in the order of their succession. The descriptions are made from the best examinations I was able to make. QUATERNARY DEPOSITS Alluvium. The Illinois river bottom, on the west side of the river, lies in the county of Bureau from three miles below Peru to the south line of the county, a distance of from fifteen to eighteen miles in length. At its upper end it is not much over a quarter of a mile wide ; at its lower, it gradually spreads out to a mile or mile and a quarter. For most of this distance there are two bottoms. The first and widest is a low flat expanse, composed of sloughs, river sand beds, finely comminuted black mud banks, boggy and mucky meadows, covered with a dense growth of wild grasses, and green scum-covered ponds, starred with water lilies. Most of this first bottom is subject to the annual overflows of the Illinois river. Very little of it is susceptible of cultivation, but where dry and high enough to be cultivated, it yields immense crops of Indian corn. The slough or lake on which the village of Trenton stands, runs up along the west side of this bottom for several miles. For part of this distance a heavy belt of bottom timber skirts the Illinois river. Some of the bogs, morasses, and sloughs in this low bottom, covered with green scum and almost seething beneath a summer sun, have a Stygian smell, and must be prolific breeding places for agues and intermittent fevers. The name Lepertown, applied to the part township lying along the Illi- nois river, is no misnomer. I do not know the depth of this black, alluvial deposit of river mud and sand, but it is quite deep, perhaps thirty or forty feet in many places. From forty to fifty feet above this first bottom of the Illinois river, and lying along its western bluff range, is another or second 176 ECONOMICAL GEOLOGY OF ILLINOIS. river bottom or terrace. This one is from a few hundred yards to half a mile or more in width. It seems to be composed of sandy and marly clays, intermixed in places with marly-mixed gravels. It is a regular river terrace. Its eastern line is the old shore of the Illinois river. The railroad track is built along this river shelf or terrace, and the traveler, from the car window, obtains a fine view of the valley of the river, stretching away with its dark ser- pentine belt of timber, and glimpses of the slow-moving, shining water. In the diluvial epoch, when the water' spread all over the low bottom, the Illinois river, lake-like in its expanse and slowness of current, must have presented a body of water larger than the Mississippi in its ordinary or even high stages of water. The lower valley of Big Bureau creek has also a narrow alluvial bot.tom, back a few miles from its confluence with the Illinois river. This bottom is narrow, crooked, and covered with timber. The de- posit is a rich, fat, marly one. A few small farms are opened in it below Tiskilwa. These farms are immensely productive. The swamp lands of Green river are also alluvial deposits. They are grassy marshes and imperfect peat moors and bogs, containing great beds of black mud, muck, and impure peat. The Loess. The Illinois river bluffs, already referred to, are par- tially made up of an imperfect Loess deposit. These bluffs rise to a height of nearly one hundred and fifty feet, and display some of the characteristics of the bluff or Loess formation. The deposit is not as plainly marked, however, as the marly, partially stratified clays and sands along the Mississippi bluffs, about Fulton. Some of the steeper bluffs present bald knobs, and light-colored marly clays exist along their sides. Between Bureau Junction and Peru there are several places where landslides have taken place, and the formation is more easily recognizable. One of these is a marked feature in the landscape. At a distance, it presents the appearance of a heavy outcrop of a white sandstone. A closer examination shows it to be a heavy bed of sliding, crawling sand. It is a white, yellow-banded sand, marly in its composition, and exhibits the most marked lines and bands of stratification. The outcrop is about thirty feet in thickness. It may be found in the side of the bluffs, near the railroad track, some three miles east of Trenton. The caving sands have crawled down the hill almost to the railroad track. This Loess formation thins out rapidly as it recedes from the bluffs, and soon loses itself among the drift clays, with which it is closely associated. These bluffs, for a part of the distance, in this BUREAU COUNTY. 177 county, show no rocky outcrops along their bases or up their ravines, but are mostly made up of Loess and Drift-clays, and sands. Drift. The usual yellow and blue clays of this part of the State lay over this county in a thick deposit. The artesian well, at Princeton, shows them to be about seventy-nine feet thick there, before rock was struck. The record of that well shows that a thin bed of rock was then struck, only three feet thick, and then a hard- pan clay was penetrated to the farther depth of one hundred and fourteen feet. There may, however, be some mistake about this; the record was poorly kept. It is more likely that the thin bed of rock was some detached mass sticking in the Drift clay, and that the real depth of these clays here is about one hundred and ninety- three, instead of seventy-nine feet. Some of the higher ridges of the prairies contain finely assorted gravel beds. This is true of that portion of the county between Sheffield and Tiskilwa. Some fair gravel beds are also opened along the railroad northeast of Princeton. But these gravels are full of marly clays and hard-pan. No coarse gravel beds and fields of bowlders were noticed. Some detached bowlders of black and flesh- colored granite were noticed at a number of places on the surface of the prairie. No beds of heavy coarse gravel were observed. The regular Drift deposits of the county belong to the lower and older Drift clays. I could observe nothing like glacial action, and the only evidences of the ice forces are the bowlders dropped from the icebergs floating over the submerged prairies. Coal Measures. On all the old geological maps of the State which I have seen, the northern line of the Illinois coal-field is marked too far south, both in this county and Henry. According to these maps, about one-half of this county the north half is underlaid by Silurian rocks. The north boundary line of the Illinois coal-field should commence at a point in the east line of Bureau county, ten miles south of the northeast corner of the county, nearly due west of Homer Station, on the Illinois Central railroad. Thence it should be drawn nearly due west, but curving or bellying a little to the south, until it crosses the track of the Chicago, Burlington and Quincy railroad, a little southwest of the village of Maiden ; thence it should bear off a little north of west until it intersects Green river at the northeast corner of the township of Gold ; thence down Green river 12 178 ECONOMICAL GEOLOGY OF ILLINOIS. to a point north of Geneseo, in Henry county; thence northwest until Rock river is reached, a few miles above Aldrich's mine, touch- ing and taking off a small corner of Whiteside county. All of Bureau and Henry counties south of this line are underlaid by lower Coal Measure deposits. A line passing through the points where coal is actually worked along the north margin of the Illinois coal-field, would pass across the State from Eock river, to the Illinois, as follows : Commencing at Aldrich's mine, on Rock river; thence southeast to Anawan, on the Chicago and Rock Island railroad ; thence nearly east on the same road to Sheffield; thence to the shaft of Robinson, Dinke & Co., near the crossing of the railroads between Wyanet and Buda ; thence north of east to Biernan's shaft, five miles east of Princeton ; thence to the shafts and outcrops about LaSalle and Peru. Coal may yet be worked north of this last line, but at all events, the coal deposits extend as far north as the first described line. It will thus be seen that over two-thirds of the county is underlaid by the Coal Measures. Having given their superficial extent, let us next obtain as good a vertical section as we can. Two artesian wells, one put down at Princeton and one at Tiskilwa, afford the best opportunities of making such a section. These wells are not always reliable, but they furnish the best data that can be obtained in this county: flection of Artesian Well at Princeton. Feet. 1. Soil, and yellow and blue clays 53 2. Sand 20 3. Clay, indurated hard-pan 3 4. Stone quality not given 3 5. Clay, called hard-pan in record 114 6. Quicksand 13 7. Hard-pan and stone '. 10 8. Gray sandstone, bottom hard 58 9. Soapstone, bluish-buff color 12 10. Thin mud vein about 1 11. Sandstone 12 12. Hard rock, which cut tools 14 13. Soapstone, of light color ? The bed of soapstone at the bottom had been penetrated to a con- siderable depth, and the work had then been suspended. Contrary to general expectation, this well penetrated no coal seam. The bor- ing is to be resumed for the purpose of trying to obtain a supply of water for the city. Section of Artesian Well at Tiskilwa. Feet. 1. Earth and soil 6 2. Hard sandstone 40 3. Brown clay 25 BUREAU COUNTY. 179 Feet. 4. Vein of sulphur % 5. Lisiht-colored slate 2 6. Black slate 1& 7. White limestone 4 8. Clayey soapstone 4 9. Hardflinty rock 4 10. White and black slate 1 11. Soapstone , 8 12. Li mestone 6 13. Sandstone ; 7 14. Alternating soapstone, sandstone, slate and clay 40 15. Flinty vein : % 16. Alternating sandstone and greasy clay 6 17. Black slate and flinty vein 3% 18. Fine white clay 2% 19. Coal 1& 20. Fire-clay 1 21. Clayey soapstone 53 22. Light-colored limestone 6 23. Hard clay and sulphuret of iron 5 24. Yellow soapstone '. 6 25. Shale, color not kept 3 26. Alternating shale, slate, etc 16 27. Clay seam 1 28. Strata of flint? y 3 29. Clay soapstone, etc 2% 30. Hard clayey sandstone... 12 31. Softer sandstone deposit t 13 32 Brown stone 4 33. White soft sandstone ? This well was bored for oil, at a time when the oil fever was at its height. Some indications of oil in a spring near by caused the enterprise to be undertaken. Of course, the hoped-for petroleum was never struck. The general similarity between this and the Princeton section will at once be seen, after the rock formations are reached. The heavy, hard sandstone, where the similarity com- menced, . is, however, struck six feet below the surface at Tiskilwa, and nearly two hundred and sixteen below the surface at Princeton. The latter well, however, was commenced on the upland prairie ; the other in the bottom of a deep ravine, with the Tiskilwa coal mines in the sides of the bluffs above the level of its mouth. Outcrops of the Coal Rocks. Natural outcrops of the rocky forma- tions are very rare in this county. No county yet examined by me shows so few. Coal valley is a little valley coming in from among the Big Bureau bluffs from the south, just above Tiskilwa. A ravine about two miles in length comes into this little valley from the west, about one mile and a half from its mouth. This ravine is known by the name of Rocky Run. A little stream tumbles down among the rocks and bowlders with a very rapid descent. The only stone quarry in this part of the county is in the bed of this tumbling stream. Huge masses of a hard, sub-crystalline quartzose sandstone block the 180 ECONOMICAL GEOLOGY OF ILLINOIS. ravine in places. Considerable stone, for foundations and other eco- nomical uses, has been quarried and blasted from these masses. They are not in situ, and are not the natural outcrop of the forma- tion to which they belong, but seem to be outliers detached from the parent strata, which are undoubtedly in situ under the clay bluffs on either side. These large outliers are somewhat water-worn. Among them are many large erratic bowlders of granite, trap, horn- blende and quartz. One or two of the granite bowlders are very micaceous. A coal seam, one foot thick, outcrops in the midst of these large detached stones, underlaid by a heavy bed of blue plastic soapstone. A section made in thia little run showed the following approximate figures : Section half-way up Rocky Bun. Feet. 1. Bluff clays, yellow and buff 40 to 60 2. Gravelly clay, full of bowlders and blocks of sandstone 15 3. Coal, stained with iron 1 L Blue, silvery, unctious soapstone lo The bottom of this soapstone is still a good many feet above the mouth of the artesian oil-well, whose section has already been given. I have called this outcrop a sandstone ; but some of its' outliers, especially farther up the ravine towards the barn of Mr. Whiting, present the character of a limestone. The rock is entirely unfossil- iferous, so far as I could see. A gocd specimen of Lepidodendron was found in this ravine a few years ago, according to local report. In geological interest and picturesque scenery, this little run is an interesting spot. I shall speak of its coal seam hereafter. The next outcrops worthy of attention were found in following the Illinois Eiver bluffs from Bureau to Peru. About two and a half miles east of the village of Trenton, along the base of the bluffs, which rise here to a bold height, the outliers of a rocky formation first begin to appear, on the farm of a Mr.'Dustin, not far from where Nigger creek comes down through the bluffs. Stone is quarried to some extent for building purposes in Trenton and on adjoining farms. The stone is a hard sub-crystalline rock, similar to that outcropping on Eocky Eun. In some places it resembles a quartzose sandstone. In the Bureau county bluffs, from Nigger creek to the county line below Peru, good quarries could be opened in many places ; but the difficulty of access to them, the sparse settlements in this portion of the county, and the great abundance of stone about Peru and LaSalle, have conspired to prevent the opening and working of the outcrops. In some instances the distinction between argillaceous BUREAU COUNTY. 181 and quartzose sandstone and argillaceous limestone, is hard to de- termine, and I may be mistaken in the true character of these out- crops at Rocky Run, and about the mouth of Nigger creek. To me they looked like a sub-crystalline clayey sandstone, if such a rock can be supposed to exist. These are the most important and almost the only outcrops in the county, except the rock strata found in close proximity to the coal seams. The coal mines at Sheffield, in the township of Mineral, are the oldest and best known mines in the county. There seems to exist here one of those local coal deposits of limited extent, so common all over the northern part of the State. It is irregularly shaped, but would be found about four miles in diameter. Sections 22, 23, 24, 16, 26, 27, 28, 34, 35 and 86, in the township of Mineral, and several sections adjacent thereto, in the township of Concord, are estimated to contain more or less coal beneath the surface.* The Sheffield Mining and Transportation Company are operating several mines about a mile west of the village, and near the railroad track. A low range of hills, facing north and east, rises from Coal creek to the high prairie lying south. Into this low hill several drifts are extended to the south and west. Some of the drifts are inclined planes extending down to the coal. The drifts are driven into the hill about one-half mile. Twenty-five or thirty feet over- head productive prairie farms are tilled. Black shale, soapstone and irregularly-bedded yellow crystalline sandstone ( ?) compose the roof, not all found associated together, but some in one place and some in another. Over this slate or stone roof is a body of indurated clay. The coal seam is underlaid by a bed of indurated fire-clay. This under-clay contains some large nodular masses of limestone, some of them kidney-shaped and some of them round, and all flat. Fine impressions of fern leaves have been found in the roof slates, if the statements of the miners are to be relied on. The coal seam itself ranges from four and one-half to five feet in thickness. A thin seam of light-colored fire-clay runs through the * These apparently local deposits of coal, occurring along the borders of the Illinois coal field, are not detached outliers, but are localities where the coal seams attain their full thickness, and may be successfully worked, while in adjacent territory they become too thin jto work, although they may attain their full thickness again within a distance of a few miles. An areaof coal land is oftenpronounced unproductive, on the evidence obtained, perhaps, by a single boring, where the drill may have struck a "horseback," or some other irregularity in the coal seam, while another boring, but a few feet from the first, would have shown the usual thickness of coal. It is by no means safe to pronounce any consid- erable area within thi; confines of the coal field unproductive, on the strength of such evidence as may be obtained by one or two experiments with the drill. A. H. W. 182 ECONOMICAL GEOLOGY OF ILLINOIS. coal seam near its middle; near the bottom some seams of shale also exist in the coal. This fixes the identity of the coal with that mined at Wataga, Galva, Kewanee, and the upper Peru coal. Prof. LESQUEEEUX says thai the Wataga coal is the same as the middle Peru seam. I have little doubt of the Galva, Kewanee and Shef- field coals being identical with the Wataga seam. The clay and slate partings in the coal are characteristic of this seam. On the general section of the coal seams of the State, this seam would belong to coal No. 6 or 7, according to Prof. WORTHEN'S reconstructed coal section, as published in the first volume of these reports, page 172. The following description and analysis of this coal is taken from the Eeport on Illinois Goal, made by Prof. J. G. NORWOOD and his assistants : Coal bright, hard, compact; fracture inclining to conchoidal; layers thin, and separated with minute seams of carbonaceous clod; contains a few thin seams of carbonate of lime; slacks on exposure to the weather. Specific gravity 1.1986 Loss in coking 47.5 Total weight of coke 52 . 5 100.0 ANALYSIS : Moisture 7.0 Volatile matters 40 .5 Carbon in cok.e 47.5 Ashes (white)... 5.0 100.00 Carbon in the coal 53.4 As a matter of general interest, I also give the analysis and de- scription of this same coal, made some years ago, by Professors PORTER and B. SILLIMAN, Jr., who occupied the chairs of Analytical and Agricultural, and General and Applied Chemistry, in Yale Col- lege, at the time of making the report, from which I take the fol- lowing extract : Subjected to a moderate red heat, it yielded, in a hundred parts, as an average of two trials- Volatile matter 29.32 Fixed carbon 64.90 Ash.. . 5.78 100.00 The specific gravity of the coal is 1.247, giving 2.103 Ibs. to the cubic yard. These results are nearly identical with those obtained from a sample of English bituminous coal (New- Castle) recently analyzed by us. The coke obtained from your coal is of a very superior quality, being firm and of high metallic luster. The amount of fixed carbon is large. It has been repeatedly demonstrated by experi- ment that the evaporative power of different coals is in proportion to the quantity of this constituent. Your coal is therefore of superior quality for the production of steam. We BUREAU COUNTY. 183 have used the coal for several days in an open grate, and find it adapted for this use. It ignites readily and burns freely, cracking open as it becomes heated. It burns to a com- paratively small quantity of ash, without producing clinker. To test thoroughly the effect ,-of a high temperature on the coal, we burned a grate full of it, keeping the blower on, until it was entirely consumed. In this case, even, the quantity of clinker or fused ash was small. In all our experiments with the coal, burning it in an open grate and otherwise, it has not contaminated the atmosphere of the room with sulphurous or unpleasant gasses in the slightest degree. Neither do we observe in the coal those layers or grains of pyrites or sulphuret of iron, such as are often found in bituminous coals, and are the source of the sulphurous fumes. By this we do not mean to say that your coal contains no sulphur. Sulphur is found in all coals without exception. But we find no reason to believe that it is present in yours in larger quantity than in 'other Western coals of established reputa- tion. We have tried your coal in a blacksmith's forge, and have the testimony of practical men to its superior quality for such use. For many purposes it possesses great advan- tages over more highly bituminous coals. It does not melt and cement, so as to render a frequent stirring of the flre necessary in order to keep up a draft. Neither does it swell objectionably on the flre. This property, and the firmness of the coke yielded, adapt your coal especially to use in founderies and smelting furnaces, for which purpose it may not improbably be used without coking. It is impossible, however, to give a definite opinion AS to this without experiments on a larger scale than we have found it possible to make. From these descriptions it will at once be seen that the Sheffield mines yield a very valuable coal. The analyses differ considerably as made at Springfield and at' Yale College ; that, however, may be owning to the coal analyzed having been taken from different Drifts of different parts of the seam. The coal sent to the Eastern chem- ists was, no doubt, the best that could be obtained from the mines. The next coal mine of interest is near the Chicago, Burlington and Quincy railroad, south of and near the track, and about two and one-half miles northeast of Buda, on section 25, in the town- ship of Concord. A small stream, and a small grove called Bilbenne grove, at this place, give variety to the prairie monotony. Coal has been detected all around this little grove, and there can be no doubt tut that there is a productive coal patch of considerable extent to be worked out here. This is but about five miles from the Sheffield digging, in a southeast direction. A shaft is sunk in the bottom of the ravine, and a drift driven into the hill on the principle of an inclined plane. Messrs. Robinson, Dinks & Co. are working these mines, operating a steam engine to raise the coal from the shaft. The shaft is sixty feet deep; the seam of coal from four and a half to five feet thick, and said to resemble the Sheffield seam in appearance and in the quality of the coal. Forty feet above this heavy seam, and twenty feet below the surface of the ground, is another coal seam about two and a half feet thick; but the coal is of inferior- quality. The shaft is used in mining coal in the lower seam, the drift for mining the upper one. 184 . ECONOMICAL GEOLOGY OF ILLINOIS. Section thirty-two, in the township of Center, is said to show evi- dences of coal, but as no coal mine is worked there, no examination was made of the place. Following on southeast in the same general course, the next coal of workable thickness is found in Coal Valley and Eocky Run, near Tiskilwa. These mines have been worked for many years. Two or three drifts have been worked out and abandoned. There seems to be three coal seams at this locality. The lower one has only been found in the boring made for an artesian oil well, at a depth of one hundred and fifty-nine feet below the surface of the ground, at the mouth of the well. It has not been worked, and in the present state of coal mining in this part of the State is of no practical value. The seam is thin; access to it is difficult; its existence was only accidentally disclosed by the oil well boring, of which a section has already been given. The next seam, called by the miners the middle Tiskilwa seam r is worked in many places. The mines are about half a mile farther up the stream, on the left bank or bluff of Coal creek ; the entrances to the drifts are fifteen or twenty feet above the level of the water in the little brook, and still more than that above the mouth of the oil well. I cannot tell the distance between the lower and middle coal seams here, but judge it to be from one hundred and eighty to two hundred feet. The principal drift into this seam has been worked a long time, mostly by Messrs. Churchill & Shaw ; the mine is nearly worked out and is abandoned at the present time. At the time I was' there Messrs. Jobling, Sleeter & Snowden had just completed a new drift a few hundred yards above the old one ; had struck the seam at a distance of one hundred and eighty feet under the hill, if I recollect right, and, so far as could be judged at that time, they were opening a very valuable mine. I have since heard that this mine is turning out an abundance of good coal. The seam is five feet thick. It can be easily drained ; there is a fair roof of black-slate ; below there is the usual bed of ordinary fire-clay. In some places soapstone takes the place of the black-slate roof. This is doubtless the seam of coal from w r hich the analysis was made by Mr. PEATTEN, while acting as Assistant in the Illinois Geo- logical Survey. The following is his description and analysis : This bed is of the same age as the middle (?) workable seam of LaSalle county, and like that bed is frequently interrupted with clay "slips." The portion of the bed examined is on L. D. Whiting's place. Coal very bright, hard, compact ; layers generally thick, and separated with carbonaceous clod, sometimes nearly indistinct ; frac- BUREAU COUNTY. 185 ture conchoidal. Contains a very few thin seams of carbonate of lime, with occasional thin scales of sulphuret of iron. Swells but little in coking. Specific gravity 1.363 Loss in coking 43 .0 Total weight of coke 57.0 100.0 ANALYSIS. Moisture 7.5 Volatile matter 35.5 Carbon in coke 48.9 Ashes (white) ... 8.1 100.0 Carbon in the coal 57.0 To this I might add that this coal makes a considerable amount of clinker and is inclined to become solid enough to clog the grate. As a steam-making coal it is hardly considered so good as that furnished by the upper seam, the clinker from which easily crumbles and runs through the grate. It is however a good coal for general purposes. Its accessibility and the ease with which it can be worked, make it a valuable coal. Going up Coal Valley about half a mile, the outcrop of the upper seam is reached. It is well up on the hill side ; supposed to be from forty to forty-five feet above the level of the middle seam. It might be possible that this so-called upper seam is but another outcrop of the coal just referred to, and that the difference in level is owing to a local disturbance ; but I believe it to be a different seam, identical with and belonging to the same horizon with the upper coal at Eobinson, Dinks & Co.'s shaft, near Buda, and Bier- man's shaft, east of Princeton. Messrs. Worthington & Marshall are working a drift at the present time at this place. The coal is from one and a half to two feet thick. Black slate and shale are found over the coal; the usual fire clay exists below it. The clay bluff overlies all to the depth of about forty-five feet. The coal is softer than the other seam ; has a reddish or rusty appearance, and cannot be worked to very great profit. The one foot exposure of coal, near the barn of Mr. Whiting, in Rocky Eun, belongs to this seam, and lies at about the same general level. The following section will give a general idea of the Tiskilwa coal seams, and associate exposures, and underlying deposits. Section of Coal Seam at Tiskilwa. Feet. In. Drift clays.... 40 to 75 Blackshale 2 to 4 Coal... 2 6 186 ECONOMICAL GEOLOGY OF ILLINOIS. Feet. In. Clays and shales 7 40 Coal 5 Alternations of shales, sandstone, etc., passed through in the boring 175 to 200 Coal 1 t Fire clay and clay shale thickness unknown. No fossils were observed in and about these coal mines, except sections of a flattened coal plant of some kind, found in the roof slates of the upper seam. These fragments had become completely impregnated with sulphuret of iron; they presented a beautiful irridescent appearance, and readily split with the grain of the plant, showing its fibrous texture. The next important coal mines are at Bierman's shaft, five miles east of Princeton, on section 17, in the township of Selby. Two seams are reached here. The following section will give an idea of this coal deposit : Section at Bierman's Shaft. Feet- 1. Usual oak land soil and subsoil 4 2. Yellow, hard, ringing sandstone .' 10 3. Soapstofle, clay, shale and other deposits 64 4. Coal soft, rusty, inferior. No. 7 2% 5. Black shale, clay and sandstone 42 6. Coal hard, bright, good quality, No. 6 5 The upper sandstone in the above section . outcrops along the banks of the creek a few hundred yards below this shaft. This coal seam dips apparently toward the northwest. The shaft is operated by a common two-horse whim. The mine is a very valuable one, and it will pay to put on a steam engine and work it strongly. Another shaft, being sunk a short distance down the creek, had passed through the upper seam, and had reached the lower sand- stone at the time I was there. The deposit, I think, is of consid- erable local extent, and ought to be more fully prospected. The coal is of excellent quality, fully equal to the Sheffield coal. The seams, I think, are identical. The drifts from Bierman's shaft run north and east a few hundred yards. Like the upper Peru seam, this is frequently interrupted by faults, clay slides and horsebacks. These latter are places where the coal gives out for short distances, and is replaced by bowlders, nodules, shales and a conglomerate mass of sulphuret of iron. The mines at Coal Valley, in Eock Island county, at Perry's, in Henry, at Tiskilwa and Sheffield in this county, and the upper working at LaSalle and Peru, all, more or less, have this characteristic feature, but are not therefore neces- sarily the same coals. BUKEAU COUNTY. 187 These are the only localities in the county where coal is worked to any extent. There is said to be a thin outcrop of coal on Nigger creek, among the Illinois river bluffs. This would be a few miles east of Bierman's shaft. If coal does exist there, it has as yet attracted no attention. There are several other localities in the county where coal is supposed to exist, but they are not worked, and have not even been thoroughly prospected. The position to which these seams should be assigned in the gen- eral section of the coals of Northern Illinois is not easily fixed. The lower vein at Tiskilwa probably is the same as the lower La- Salle vein, being No. 2 of the section ; and this is the only place, so far as I know, where a third vein has been discovered in the county. The seam worked at Sheffield; the lower seam at or near Buda; the middle seam at Tiskilwa, and the lower or worked seam at Bierman's shaft, are all identical with each other, I think, and are identical with the upper Peru and LaSalle coals. This seam, according to the new section for Northern Illinois, would belong to coal No. 6. The upper seam at Tiskilwa, at Bierman's shaft, and at the shaft of Robinson, Dinks & Co., is probably the equivalent of coal No. 7 of the new section of the Illinois coals. These seams are assigned to the horizons of the LaSalle coal seams, not onv palseontological evidences ; characteristic fossils seem to be scarce at all 'the localities examined ; the coal seams themselves, however, and their associate rocks and shales, seem to justify such classifi- cation. The position of the Sheffield coal, near the surface of the ground, and no seam being found above it, would seem to identify it with the upper instead of the middle seam ; but its place without doubt, I believe, is with the coals of No. 6 in the section referred to. The general level of these seams varies greatly. The railroad track at Sheffield is eighty-eight feet above, and at Tiskilwa it is sixty-six below, the level of the surface of Lake Michigan. Estimating from the position of the coal seams, as compared with the railroad track at these places, there must be a difference in the level of the coal of from seventy-five to one hundred feet, in a lineal distance of some twenty miles, showing a dip of about five feet to the mile to the southeastward. Silurian Formations. There are no exposures or outcrops of the Silurian rocks in this county ; but the northern one-third of it is underlaid by these rocks in about the following order : 188 ECONOMICAL GEOLOGY OF ILLINOIS. The Trenton or Blue Limestone, These rocks outcrops rather heavily at Homer, about two miles east of the Bureau county line, in LaSalle county. They doubtless continue the underlying rock west, or a little south of west, along the north line of the coal field, until they sink beneath the Coal Measures opposite to Princeton, and extend north- ward nearly to the C., B. and Q. railroad. The Galena Limestone. This limestone outcrops at Lee Center and near Sublette, in Lee county, and is probably the underlying rock in that part of Bureau county about and on both sides of Bureau creek, and between that creek and Green river, and north of the Coal Measures, with the exception of some elevated ground about "Dad Joe's Grove." The Cincinnati Group. These shales would doubtless be found underlying the grove just named, and may also underlie small patches in the northwest corner of the county, west of the Green river swamps. Economical Geology. Coal. From what has already been said, in speaking of the coal seams and their outcrops, it will be seen that the coals of Bureau county are an important element of county wealth, and minister largely to the convenience and well-being of its citizens. I have no means of estimating the present amount of coal mined each year in the county. The Sheffield mines have been worked since 1853. Two hundred and fifty thousand tons of coal are supposed to have been mined and sold during that time at these mines. They are being worked extensively at the present time, and their supply is by no means exhausted. Thousands of tons have doubtless been taken out by farmers and land-owners, in small quantities at a time, of which no account has been rendered. The coal-field actually known to exist here has hardly commenced to be worked over, and may be found to extend much farther east, south and west than is now sup- posed. The Buda shaft is worked strong enough to employ a steam engine, and is yielding at the present time a large amount of good coal. Other shafts, in course of time, will be put down here. There is evidence that coal underlies several miles in extent of surface around the grove where the present mine is worked. The necessities of the country, and the ease with which shafts reach this good BUREAU COUNTY. 189 workable seam, insure more extensive operations at this locality. By the B'uda shaft, I refer to the one between that place and Wyanet. Almost the same can be said of the locality at Bierman's shaft. I am satisfied this is a valuable field of coal, of considerable extent, of easy access. It will be worked extensively at an early day, and will afford a large supply of excellent coal. The Tiskilwa coal-banks are old banks, having been worked for many years. The amount of coal taken therefrom is not known, but they have at no time been worked as strongly as the mines at Sheffield, and the supply of coal has been much less. I am uncer- tain as to their future productiveness. For a time they were con- sidered as partially worked out, but the heavy seam found in the new bank of Messrs. Jobling, Sleeter & Snowdon seems to show that the supply of coal is by no means exhausted. This discovery will probably add new impetus to coal mining in this locality. * There are many other localities in the southwestern and south- eastern portions of the county, where shafts sunk to a moderate depth would strike coal from four to five feet thick. Along and among the Illinois river bluffs there is no reason why valuable coal deposits may not be found. Borings along the base of these bluffs ought to disclose the middle and even lower Peru coal seams ; and if the ravines were carefully traced to their sources, outcrops and exposures of the upper seam would doubtless be detected under the talus and along the little streams. Bureau county already produces coal enough to supply in great part the home demand, except a considerable amount of transported coal used in the larger railroad towns. As fuel becomes scarce, and the demand therefor greater, the coal interests of the county will be more fully developed. The hungry maw of the iron horse, the iron stomachs of many steam boilers, .a great increase among the people of coal stoves and coal-burning appliances, will constantly increase the demand for coal. These hidden sources of wealth and prosperity will then be looked up more carefully, and the supply will be found adequate to the increased demand for many years to come. Building Stone. So far as at present known, stone quarries are few, and the home supply of stone for building and other economic purposes is quite limited. I have already named the localities where stone is quarried, but even at these localities the supply and quality are both of such a nature as to make the quarrying of rock an item of small economic value. Heavy quarries could be opened below 190 ECONOMICAL GEOLOGY OF ILLINOIS. Peru, but access to them would not be easy. The difficulty is largely remedied, however, by the ease with which stone from Peru and LaSalle, and from the marble quarries of Athens and Joliet, can be shipped on the intersecting railroads to convenient and accessible points all over the county. Lime from the banks of the Mississippi, about Eock Island and Port Byron, and from the stone ledges towards Chicago, is also readily obtained. Clays and Sand. The heavy Drift deposits over the county contain abundant supplies of sand and the common kinds of clays. Common red brick of good quality can be made at reasonable expense, and sands for mortar dug from almost every township. The facilities for building are thus within the reach of all. No minerals of economical value exist. Peat. Several peat beds exist in the Green river swamps in the township of Gold, and in one or two adjoining townships. Some of this peat is of fair quality and of considerable depth. But in the present state of our knowledge as to the manufacture of peat fuel, none of these beds possess very great value for burning and heating purposes. They, together with their associate muck beds, will some day possess a value as a fertilizer of the surrounding prairie soil. Agricultural and Horticultural Geology. Enough has already been said about the agricultural resources and capabilities of the county. They do not differ greatly from those of surrounding counties. Perhaps they are better than those of most other counties in this part of the State. The soil seems to have in it a little more fine silt to be lighter and warmer than that of some of its neighbors. As a consequence of this, it is largely and uniformly productive of the sta'ple products of Northern Illi- nois. Fruits, and especially the hardier varieties of the apple, do re- markably well. The orchards about Princeton are among the oldest and best in Northern Illinois. According to the reports of the various ad interim committees of the Illinois Horticultural Societies, the apple orchards of Princeton are among the best in the State. I know not to what extent grape culture has been carried on in the county; but the nature and properties of the soil would justify the planting of the vine to a large extent. Some of the Illinois Eiver bluffs on the east side of the county could be turned into profitable vineyards. Wine-making might be made remunerative in many places where BUREAU COUNTY. 191 the land is now considered almost worthless. The small garden fruits, such as gooseberry, currant, strawberry, raspberry, etc., do well almost anywhere in this part of the State, and of course flourish luxuriantly in the warm light soil of this county. EXPLANATORY NOTE. The geological map of Northwestern Illinois, prepared by Mr. Shaw, to accompany this report, including a section of the formations outcropping on Rock river, was in the hands of the Western Engraving Co., in Chicago, at the time of the great fire, in October, 1872, and was utterly destroyed. The map is often referred to in the preceding pages. A. H. W. CHAPTER XI. HENRY COUNTY. Henry county is bounded on the north by Whiteside county and Rock river, on the west by Rock Island and Mercer counties, on the south by Knox and Stark counties, and on the east by Bureau county. It is a very large county, being thirty miles long and thirty miles broad, and lying in the form of an exact square, with the exception of about two townships cut off from the northwest corner in a sort of triangular-shaped piece, by Rock river. It consequently contains about eight hundred and twenty-five square miles. The surface of the county is made up mostly of a high, rolling, fertile prairie, in places breaking into rough ridges and ravines. For a few miles back from Rock river, in the northwestern part of the county, and about Minersville, the land almost approaches the char- acter of barrens, being interspersed with ravines and elevated ridges, partially covered by a somewhat stunted growth of oak timber. About the northeastern corner, the prairie becomes somewhat sandy, rising occasionally into white hillocks of sand, cut into picturesque shapes by the prairie winds. Across the northern part of the county, the broad valley of Green river is level, and chiefly composed of swamp lands, of which there is estimated to be some fifty thousand acres. This valley is rather a low, wet, swampy prairie, than a regular river valley. Green river enters the county from the east, about eight miles from the northeast corner, and flows almost directly west across the county, through the second tier of townships, until it enters Rock river, a few miles southwest of Colona. For a part of this distance, it is rather a succession of swamps than a river. At other places, it is a broad sheet of stagnant water, almost lost among the reeds, rushes and tall grass; but towards its outlet into Rock river, these waters " gather into a stream of considerable ' tfiLO HENRY COUNTY. 193 size and depth, with scarcely an appreciable current a slow, lazy, stagnant stream, oozing along amid a deposit of black, greasy-looking mud green with its coat of August scum, a very Styx of a stream, on whose filthy, scummy surface intermittent fevers and agues seem to play, like half-concealed, restless ghosts. Such a stream I have never seen before, not even excepting the liquid mud of the Peca- tonica, which latter stream has a decent current or flow, when compared with Green river. And yet I would not convey the idea that Henry county is an unhealthy county. The salubrious air of her broad prairies quickly neutralizes any miasmatic influences thrown off by this local nest of fevers. If Pandora's box itself were opened on one of our broad, high prairies', the spirit of Health would drive thence the whole brood of ills and woes and diseases as they swarmed forth. The Edwards river flows across the southern part of the county, in almost the same relative position that Green river occupies in the north. The surface between the two, which is from twelve to fifteen miles wide, is a high, dry, rolling prairie, under a good state of cultivation, the water-shed of the two streams running not far from the middle of it. The Edwards river has a bottom averaging perhaps a mile in width. This is low, but not so wet or swampy as That of Green river. Both streams are almost timber- less ; the latter almost dries up in the summer season, but when swollen with rains, it is a formidable body of water. The country rises rapidly from the Edwards river bottom, assuming almost the form of a low range of undulating bluffs along its south side. The southern part of the county is of the same general character as that between these two streams, except the southeast corner township of Kewanee, which is somewhat broken, and covered with timber where most broken. Spring creek is a deep little prairie brook, which runs towards the north, and falls into Green river twelve miles from the eastern line of the county. These are the only streams of conse- quence in Henry county. In addition to the scattering timber about the northwest and southeast corners of the county, in the townships of Kewanee, Colona and Hanna, the broad expanse of prairie is diversified by a few beautiful groves, many of them sadly marred by the settler's axe. Among these are White Oak Grove, south of the village of Andover; Sugar Tree Grove, east of Cambridge, the county seat; Hickory Grove, not far from Galva; Bed Oak Grove, in the town- ship of Weller; a small grove near Council Hill; and several small barren groves, whose names I do not now recollect. These furnish 13 194 ECONOMICAL GEOLOGY OF ILLINOIS. a fair supply of timber for their immediate neighborhood, but will become exhausted in process of time, unless timber-growing receives more attention on our prairies. In an agricultural point of view, this county is hard to excel. Such a large proportion of the surface is under cultivation, that its grain-producing powers must be immense. Such being the case, wealth, and a high state of prosperity, are found to characterize its citizens. Its groves ; its rolling fertile prairie lands ; its remarkable marshes along Green river, being a continuation of the famed Winnebago swamps ; its few sand-hills ; and its unequalled Green river, are the mosi prominent characteristics of its surface topography, and do not differ materially from those of adjoining counties north and east. Geological Formations. These consist of the usual Quaternary deposits, the lower Coal Measure series, and some low outcrops of the Hamilton and Niagara limestones. The geology of the county, at first thought, appears quite simple; but the paucity of stone quarries, and workable out- crops, over most of the county, makes the problem more difficult than one would at first imagine. The best section I can construct will give the formations about as follows : General Section of County. Feet. Alluvial deposits and Drift clays 50 to 100 Lower Coal Measures 250 to 300 Hamilton (Devonian) limestone 20 Niagara or LeClair limestone 15 In this section a very marked hiatus of Illinois rocks will be ob- served between the Hamilton limestone and the Coal Measures. Niagara Limestone. In the bed of Rock river, where it first touches the northwestern boundaries of Henry county, and from thence about half way to Cleveland, the soft, fine-grained, yellowish LeClair limestone shows itself, and is quarried during low stages of the river, at one place to a considerable extent. The Coal Measures at Aldrich's, and Johnson & Kent's coal mines, rest directly upon this member of the Niagara limestone. Except this limited outcrop in the banks and bed of Rock river, this formation cannot be said to be developed in the county. At ordinary stages of water in that stream, the outcrop would hardly be detected. With the exception of a few encrinite stems, no fossils were noticed in it. HENRY COUNTY. 195 Hamilton Group. On descending Bock river from the Niagara out- crops just mentioned, the lower division of the Hamilton limestone is next discovered, commencing in the bed of the river about a mile and a half above Cleveland, and continuing as the river flows to the west line of the county, and thence west at intervals across Eock Island county, A short distance above Cleveland, and two or three times below it, in a distance of three miles, a short axis of upheaval appears to extend from the river almost south across Kock river bottom, which is here three-fourths of a mile in width, and runs under the bluff line. At these places the Hamilton limestone comes to the surface of the ground, where the rains or little streams have removed a few feet of the top soil. These axes, or undulations, rise twenty-five or thirty feet above the low bottom land of Eock river. Between are depressions or troughs, filled with Coal Measure deposits. The heavy seam of coal, worked so extensively at Cleve- land, rests in one of these basins, and extends half way across Eock river, resting almost directly on the Hamilton limestone. The top of the axis spoken of above, east and west of the coal basin, is higher by several feet than the coal seam. Southward, however, the Coal Measures continue uninterrupted under the bluffs to Coal Valley and the Minersville mines. These natural outcrops of the Hamilton limestone are massive and solid in their structure. The stone breaks with a smooth conchoida| fracture, almost resembling polished marble. On fresh fractures the color is a beautiful bluish-white or pale dove color. A semi-trans- parent, splintery, horny appearance was noticed in some cases on breaking a rock to pieces with smart blows of the hammer. No fossils were observed. Indeed, the lower portion of this rock is almost devoid of organic remains. While making these observations, parties were engaged in boring an artesian well, two miles above Cleveland. Prospecting for petro- leum and coal was the object of the boring. Any practical geologist could have told the proprietors that their hopes would not be real- ized, and that their labor and money was being foolishly expended. In connection, however, with the geology of this part of the county, they made an interesting hole in the ground, of which the following is the best section I could obtain : Section of Artesian Well near Cleveland. Feet. 1. Black earth, alluvial deposit 12 2. Black and dark-colored shales and slate 18 3. Dark limestone, cap rock of Cleveland coal 3 4. Limestone (probably Hamilton and Niagara) 398 5. Soft shale (probably Cincinnati group) 77 196 ECONOMICAL GEOLOGY OF ILLINOIS. At this depth the drill struck a sharp, hard rock, with sandy grit in it. How much deeper this well was put down I have not ascer- tained. Another artesian well was put down, just north of Kewanee, to a depth of six hundred feet, in search of 'water, I believe. No accurate record of strata bored through was kept. Three hundred and fifty or four hundred feet of the bottom penetrated a hard, light- colored limestone, being perhaps the same formations passed through in the lower part of the Cleveland well. This, however, is only conjecture. Coal Measures. "With the exception of the formations just described, the whole county is underlaid, below the usual drift deposits, by the lower Coal Measures. It is quite difficult to obtain a correct knowledge of the local extent of particular deposits, on account of the scarcity of outcrops. In other counties the railroads and the streams nearly always expose the upper rock formations, and give, in their cuts and banks, well marked outcrops. In Henry county the railroads only afford a few clay cuts, not once exposing any rock formation. The river banks of Green and the Edwards are, if possible, still more unfavorable for geological examinations. Not once, so far as I know, do the banks or bends of these streams afford good outcrops of even the sandstones and limestones of the Coal Measures. Large por- tions of the county are utterly without stone quarries of any kind. In a few places fragmentary outcrops of rotten sandstone, or defective shaly limestone, occur ; and in a very few localities limestone or sandstone is quarried in abundance. I shall first speak of these outcrops, before attempting to describe and trace the coal seam. Sandstone. Overlying the lower coal and its roof of black shales and dark limestone is a heavy deposit of coarse-grained sandstone. The rock is gritty, not very hard, of a creamy-brown or dirty-whitish color, and greatly resembles the sandstone deposit north of Morri- son, except that the soapstone seams are wanting. Three miles below Cleveland, in the face of the river bluffs, but near their base, and at several places below or farther down the river, the outcrop is conspicuous, and has been quarried for local uses. The outcrops are partly hidden by talus ; but the sandstone at these localities seems to be from twenty to thirty feet thick. This same sandstone, on a line westward, outcrops heavily at Camden, at Hampton, and opposite the latter place in Iowa. At the latter place some fine specimens of Lepidodendron were found some years ago. The prin- cipal outcrops about Cleveland are on sections 20 and 35 of town- HENRY COUNTY. 197 ship 17, range 1 east. At Moline it also outcrops, and at Hampton it covers a thin coal seam or trace of coal.* At Camden the coal seems to be above the heaviest body of sandstone. At Hickory Grove there is a light sandstone outcrop, not very thick ; stone poor quality; quarried by neighboring farmers. In the valley of Green river, up the latter valley, and into the bluffs of Mineral creek about Minersville, the same bed of sandstone shows itself in several places. The outcrops here run from seven to twelve and twenty feet thick. On section 3, in the township of Munson, and not far from Cambridge, some poor sandstones are quarried. In the shaft of the Platt Coal Company, just east of Kewanee, thirty feet of heavy sandstone was struck immediately overlying the coal se*am at the bottom of the shaft, but this bed is about a hundred feet below the surface.! In the vicinity of Bed Oak Grove a thin, rotten, Car- boniferous sandstone has been quarried by the farmers, and used for farm purposes. One well was walled with this material. The wall decayed or rotted down, and the well caved in after it had been in use for a series of years. On section 20, on Spring creek, in the township of Atkinson, there is a small stone quarry, but my notes on its characteristics have been misplaced or lost. These are the best tracings I have been able to make of this bed of sandstone. Its place in the geological section of the county seems to be above the heavy, lower, workable seam of coal, some- times separated therefrom by shales and limestone, and sometimes appearing to rest almost directly on the coal. Its position is by no mean's constant, however. It is also almost unfossiliferous. A few tracings of Catamites and Lepidodendron were the only organic remains I couM find in this deposit. Limestone of the Lower Coal. The "cap rock" over some of the coal mines is a dark-colored, almost black, and sometimes shaly limestone, in which is frequently found a small and beautiful Pro- ductus. The coal seam at Aldrich's mine is overlaid by a thin stratum of shale, which is capped by a hard, blue, shelly limestone. This limestone is quarried in small quantities here, and sold at a high price to neighboring farmers. At Cleveland the coal seam is stripped of its superficial covering over several acres in extent. The * NOTE. We think Mr. Shaw has here confounded two distinct beds of sandstone that at Camden begin below the main coal seam, instead of above it. The sandstone above the coal is a much more durable, and is generally a harder rock than the bed below. A. H. W. t NOTE. This sandstone overlies coal 5 or 6, and is at least one hundred and fifty feet above either of the beds outcropping in the vicinity of Camden, Moline or Carbon Cliff. A. H. W. 198 ECONOMICAL GEOLOGY OF ILLINOIS. limestone is more massive here, not quite so dark in color, and rests almost directly upon the coal. Hundreds of cords of it are stripped from the coal. The deposit is from one to two feet thick, and great quantities are sold at remunerative prices. Large num- bers of the heavier stones thus quarried are to be used in the rail- road bridge to be built across Eock river at this place. Immense slabs, more than a foot in thickness, obtained at the lower opening, are piled over an open space, ready to be transferred to the piers in the river. Some of these show signs of crumbling round the edges, as if the tooth of time had gnawed into their surface. We doubt whether they will prove entirely satisfactory for railroad masonry. Above this massive strata, and separated from it by from four to seven feet of shales and black, hardened carbonaceous mud, is another strata of lighter-colored, thin-bedded, shaly limestone, which is also corded up and sold for lighter masonry. The supply of stone thus obtained at these coal mines is very considerable. About Minersville the same limestone is found in connection with the coal seam, and a section here would be very similar to the Coal Valley section, except the sandstone above spoken of. Along the banks of Geneseo creek, a little southwest of the city of Geneseo, there is a very curious outcrop of stone, which has been worked to some extent in former years. The top of the stratum is a sandstone for about two feet in depth- It then gradually changes into a blue, compact, or dark-colored limestone, having a nodular or concretionary appearance. The whole rests on several feet of compact, hardened carbonaceous mud. But the most curious deposit in this interesting locality is a thin stratum of "cone in cone," out- cropping in the yellow-clay, several feet above the top of the sand- stone. The stratum is from two to four inches thick, has a woody or fibrous texture, the grain running vertical to the plane of strati- fication ; on being dug from the ground it falls into small blocks, having the appearance of wood split from a thin section of a large tree. In one or two of the low, rain-washed hills in that vicinity, I noticed this same outcrop, with no signs of the underlying rocks. Large quantities of this "cone in cone" have been gathered up for cabinets. Its resemblance to petrifactions of wood is very complete. The Coal Seams. In the northwestern part of the county there is one heavy coal seam, well developed, and worked to a large extent. In the southeastern part of the county, and extending up through its central portion, there are two seams, the lower of which is largely mined. Commencing with the former, and at the outcrop highest up Eock river, within the county limits, we find ourselves at Aldrich's HENKY COUNTY. 199 mine, on section 24, township 18, range 2 east. The coal is here about four feet six inches thick. It is overlaid by a few inches of dark shale, and this is in turn capped by the thin stratum of black limestone, spoken of above. A bed of ordinary fire-clay lies under the coal. The mine is opened into the point of a hill, up a wooded, romantic ravine, about one-half mile from Eock river, which here washes the base of the bluffs. A steam engine pumps out the water and draws the coal-cars up an inclined plane. The drift extends toward the south at a heavy dip near its opening. The mine has been worked for many years. The coal is a bright, moderately hard, thin-seamed coal, with carbonaceous clod between the seams, and vertical markings of carbonate of lime in the perpendicular openings. The following analysis shows its composition: Specific gravity 1 .261 Loss in coking 43 . 1 Total weight of coke 56.9 100.0 ANALYSIS: Moisture -. 6.0 Volatile matters 37.1 Carbon in coke 49.9 Brown ash 7.0 100.0 This analysis was made for the State by Mr. PRATTEN, I believe, and gives the general character of the coal in the northwestern part of the county. An approximate section at this coal mine gives about the following figures : Feet. In. Drift claysof bluffs, light color 50 to 70 Dark, shelly limestone 2 Shale and black slate 6 Coal (No. 1) 4 6 Fire-clay 10 All above the water level of the river. , Half a mile below Aldrich's mine is the drift of Messrs. Johnson & Kent. The upper part and outer edges of the seam here pass into a very solid, shining cannel coal, with smooth surface and conchoi- dal fracture. Messrs. Johnson & Kent believe the seam is not iden- tical with the one worked at Aldrich's mine. The roof is of soap- stone and shale, and there are some indications of two seams, ten. or twelve feet apart, but approaching each other under the hill. There is, evidently, some local displacement here, and probably a local separation of the seam, such as is witnessed occasionally in working the Coal Valley seam. 200 ECONOMICAL GEOLOGY OF ILLINOIS. The next important workable locality is at Cleveland. Here, most of the coal is quarried, not mined. The surface deposits are stripped off, exposing the seam, which is from four and a half to- five and a half feet thick. The quality of the coal is similar to that at Coal Valley, except that it is a little better. The ash is not so red, in fact is almost white, and this is probably the better steam coal. Section at Cleveland, from the top of Hock River Bluffs. Feet, 1. Bluff clays of the drift 50 to 60 2. Whitish-brown, coarse sandstone 20 to 25 3. Gravel bed of ochre color 2to & 4. Carbonaceous black shale 5. Black limestone 2' 6. Coal seam '. 5 7. Fire-clay 12: 8. Hamilton limestone Bottom. Three or four mines are being worked in close proximity to each other. Taylor Williams has a steam engine in operation, and he both strips the seam and runs slanting drifts into it. Mr. Stokes and Mr. Jefferson Taylor also mine to some extent. The basin or hollow, between two uplifts of the Hamilton limestone, in which this Cleveland coal seam is found, is narrow at the place where the mines 'are worked, being only a few hundred rods wide, and coming to almost a point in the bed of Bock river. The coal seam widens out towards the south, but becomes thin where it runs under the river bluffs. Still farther south, and about two and a half miles- from the Cleveland coal quarries, is the Green Eiver valley, which intersects the Eock Kiver valley a few miles below. This Green River valley, for several miles round Colona, is all underlaid by the Cleveland coal seam. The south slope of the bluff range between Eock river and Green river at this place, where prospected by bor- ings, also shows the seam or traces of it, at many places. The same seam outcrops and is mined extensively on Mineral creek far- ther south, and at Coal Valley, southwest a few miles. On the Green river bottom the underlying rock the cap of the coal seam is from seventeen to twenty feet below the surface. The seam at Cleveland furnishes one ton and a half of coal to the superficial square yard of its surface. The section there made will give a gen- eral idea of the Coal Measures on Mineral creek, farther south, and for the rest of the northwestern part of the county. No two sec- tions, of course, would be exactly alike; but the resemblance would be very marked. HENRY COUNTY. 201 The superficial extent of coal lands, underlaid by this coal seam, extending from Cleveland around by Mineral creek, Minersville, Coal Valley, and Green Kiver Valley, so far as now prospected, contains perhaps some forty thousand acres. On a railroad and coal land map, made by the chief engineer of the railroad about to be built along Eock river, some fourteen sections and parts of sections are marked as underlaid by coal in township 17, range 2 east ; in town- ship Yt, range 1 east, some twenty-two sections and parts of sec- tions are similarly marked ; in township 17, range 1 west, some ten sections and parts of sections are marked as containing coal under- neath ; in township 16, range 1 west, five or six sections are simi- larly marked; in the same township and range east, three sections are coal lands ; in township 18, range 2 east, some ten more sections are supposed to be underlaid partially by coal. These east ranges are in Henry county ; the west ones are in Eock Island county. The Cleveland mines are in township 18, range 2 east. Other sections will, no doubt, be found containing coal in this vicinity. Of course, all the above marked coal lands are not underlaid by heavy coal deposits. Wherever coal or its traces were detected by the engineer in charge Mr. J. C. Abbott, to whom I am under many obligations for favors extended the same was marked coal lands on the map. My own personal examinations confirm the general correctness of this map. The following worked mines in this coal field should not be passed over without notice. On or between sections 17 and 18, township 17, range 2 east, Mr. Shepherd is successfully operating several shafts; on section 22, township 17, range 1 east, Perry's mine is also now in successful operation ; Glen's mine, on section 20, in the same town and range, and some mines on section 21, township 17, range 1 east, now are or have been successfully worked. The seam is from four to six feet thick in this group of mines. It has an easterly dip, and appears to be lower at Shepherd's mines than at the mines of Mr. Perry. In one of these mines, where a drift is driven into the t seam, the coal is separated into two bodies, the upper three feet thick, the lower two feet, separated at the outcrop by seven feet of clay part- ing. These two parts of the seam approach each other under the hill, and unite in a distance of about six hundred feet. Shepherd's mines are located about two miles south of Green Eiver Station, on the railroad. He is operating two shafts, and driving one drift mine. The shafts are sunk near the base of Min- eral creek bluffs. The roof here is stone, same as at Cleveland. 202 ECONOMICAL GEOLOGY OF ILLINOIS. The shafts are about sixty feet deep. The coal seam is thickest on bottom or low land, and thins when followed under the hills, same as at Cleveland. One shaft is operated by a steam engine, one by a gin; both have what the miners call a "sump" in the bottom, for convenience in lifting water out of the mines. The Drift is an in- clined plane, extending from the surface to the level of the coal. The heavy, overlying sandstone is higher above the coal than at Cleveland. The shafts and drifts both extend into the same seam. The coal is supposed to be stronger and duller in color than that mined at Cleveland. In Shepherd's mines there is a black shale in places below the coal. At Minersville, the mining was all done by driving drifts into the seam from and near its outcrops. These mines are well worked out. Others may be found, when, the demand for coal becomes greater. The competition, at the present time, between Cleveland and Miners- ville coal on the one hand, and Coal Valley coal on the other, is spirited. The latter has a little, and but little advantage, in the item of transportation to market. Perry's mines, almost adjoining the latter mines, still furnishes coal in paying quantities. This mine is also reached by drifting into the coal seam. The most noticeable feature here is the basins or "horsebacks," tilled with a conglomeration of nodular masses of clay and sulphuret of iron, which are characteristic of this mine. Some of them are several yards in extent. The seam under Green river and its valley, in the townships above named, contains a great deal of coal; but the roof is poor. This has prevented its being strongly worked. From what has been said, it will now be seen that there is a large supply of coal stored away in the northwestern part of Henry county, for the present and for future generations. The mineral resources of this part of the county will not soon be exhausted, but will, as they now are, continue to be a source of wealth and ma- terial prosperity to the county. Another heavy coal deposit lies in the southeastern part of the county about Galva and Kewanee. Between this and -the Cleveland and Mineral creek mines, and over a diagonal strip across the county from the northwest to the southeast corner, which averages from ten to fifteen miles in width, coal has been found in many places. The seams, however, are thinner than at the two corners. Some of the shafts have been abandoned, and some never were worked at all. I propose to briefly notice some of the coal mines discovered HENRY CO.UNTY. 203 in this portion of the county, before describing the important coal mines about Galva and Kewanee. About one and a half miles northwest of Geneseo, there is an abandoned shaft, where a coal seam from one and a half to three feet thick was found at a depth of about sixty feet. This, I believe, is the old Allen's mine. Indurated clay, limestone and sandstone were all penetrated in sinking the shaft. The coal was of good quality ; bright iridescent in color ; hard, even fracture, and rbom- boidal cleavage. The seam was considered too thin for profitable working. At Atkinson, the next station east of Geneseo, on the Eock Island and Chicago railroad, the well dug to supply the large steam mill standing near the depot, passed through a seam of coal three feet .thick, and twenty feet below the surface. One-half mile east of this well there is a shaft still worked, out of which has been taken about ten thousand bushels of coal. The seam is here three and one-half feet thick, and twenty-two feet below the surface, and is operated by a horse gin. There is in this locality a good slate roof over the coal, ten feet thick, and it is underlaid by a bed of fire-clay. About four miles northwest of Cambridge, in the township of Oscoe, Mr. A. A. Crane has put down a coal shaft, striking a seam from thirty-two to thirty-six inches thick, at a depth of eighty-seven feet. The seam appears to thin out towards the north and thicken towards the south. On the farm of Samuel Dixon, in Munson township, eight miles east of Cambridge, coal is mined to some extent, the seam being the same as at Atkinson, and twenty-four feet below the surface. Two miles south of Cambridge, a shaft was b'eing put down when I was there. A boring previously made was reported to have indi- cated coal, at a depth which I do not now remember. Coal is mined in this vicinity about Bound Grove, equally distant east from Cambridge and north from Galva, and in considerable quantities. It is hauled in wagons to Cambridge and over the sur- rounding prairies, and thus finds a ready market at the mines. In a few more places over this broad strip of country between Cleveland and Kewanee, coal has been discovered; but sufficient has been said to indicate the general character of the seam here mined. I come now to the most extensively worked locality in the county, and perhaps the heaviest deposit of coal within its limits. Galva and Kewanee, both in the southeastern corner of the county, but a few miles apart, are widely known as coal mining localities ; but at the latter place the mines are worked to much the greatest 204 ECONOMICAL GEOLOGY OF ILLINOIS. , extent. Five or six shafts are put down at Galva, known as the shafts of Messrs. Knox & Co., Cummings, Johnson, Lindsey, and Barnum. The following section, made at one of them, illustrates the character of all. They are in a group, within a radius of a mile or two, and are as much alike as coal shafts usually are, pene- trating the same seam, and put down near together through essen- tially the same formation and superficial deposits. Section of Galva Coal mines. Feet. 1. Yellowish Drift clay 32 2. Hard rock, bottom softer and sandy 12 3. Soapstone, top light-color, bottom dark-color 14 4. Black or dark-colored slate 2 5. Coal, with clay seams No. 6 4 6. Fire clay about 9 The coal here is of good quality, and similar to the Kewanee coal. The seam is probably identical with coal No. 6, of the general sec- tion of the Illinois Coal Measure. At Galva the clay and shale partings are not so well marked as at other points, and at some of the shafts indications of cannel coal may be seen along the top of the seam. At Kewanee, much capital is employed in the coal mining busi- ness. During the past year (1867) fifty-three thousand tons were raised here, of which thirty-two thousand were shipped on the Chi- cago, Burlington and Quincy railroad to various points, fourteen thousand were used by the railroad company, and seven thousand were used for home consumption in Kewanee and neighborhood. The revenue thence derived amounted, during the year, to over one hundred and forty thousand dollars. The productive 'mines are within a radius of three miles north and east of the town. Within this small area some eight shafts have been put down, and twenty drifts driven in. The shafts are sunk from the general level or face of the country; the drifts are driven upon the outcrops in some deep ravines, passing up from a good sized brook three or four miles north of the town. The face of the country, among these mines, is rough, and covered with a scattering growth of barren oak timber. The shafts are operated by the following companies and indi- viduals : The Platt Coal Company, Messrs. Walker & Co., Breckens & King, McCartey & Kirby, K. Murchison, J. C. Bowerman, H. Martin, W. S.'Carnly, and one or two others of less note. Of these, the Platt Coal Mining Company, whose mine embraces about one thou- sand acres of land, located one mile east of the village, does by far the largest business, and by some arrangement handles and markets , HENRY COUNTY. 205 all the coal dug in all the mines in this vicinity. Their shaft is near the railroad track, and they have a very convenient mode of loading the coal into the cars. At the depot, there is also a large elevator-shaped building, used for the purpose of feeding passing locomotives ;with their supplies of coal. A section of these mines, made at the Platt Coal Company's shaft, is as follows: Feet. 1. Soil, subsoil and yellow clay 5 2. Oily looking quicksand 20 3. Soapstone, light and dark-color 25 4. Upper coal seam No. 7 2% 5. Fire-clay 10 6. Soapstone ? 7. Sandstone, same as at Galva 30 8. Middle coal seam No. 6 .^ 4)6 9. Alternating soapstone and sandstone 80 10. Carbonaceous shales and coal traces (No. 5 ?) a few inches. The four and a half foot vein is the same as the Galva seam, and is, probably, identical with the upper seam at LaSalle, and with coal No. 6 of the general section of the State. The upper seam, some forty-two and a half feet above the lower, is perhaps No. 7 of the same section. The lower eighty feet of the foregoing section was prospected by boring an artesian well in the bottom of the Coal Company's shaft, and ought to be regarded with some doubts as to whether it shows correctly the indications of coal in the bottom. The bed of quicksand or shifting sand, No. 2 of above section, was struck near 'the depot, in a shaft now abandoned. The supply of coal at Kewanee and vicinity is very large, and will not become exhausted for many years. Newly discovered mines will replace those worked out, and the revenue derived from this deposit of mineral wealth will build Kewanee into a place of con- sequence. In Norwood's report upon Illinois Coal, I find a description and analysis of cannel and bituminous coal, taken from the same seam, at a place then called "Serrell's mine," which it may be well to insert, in this place, for convenience of reference : Serrell's Mine, Kewanee. Thickness of the bituminous portion of the bed, four feet, underlaid with fire- clay. Coal bright and dull in alternating layers; hard, compact, fracture tolerably even. Con- tains thick seams of carbonate of lime, which cross each other at right angles, causing the coal to break into slightly irregular cubes. Has sulphuret of iron disposed both hori- zontally and vertically. The layers of coal are thick and separated with carbonaceous clod. Coke very bright and good, but swells in coking. Specific gravity 1 .232 Loss in coking 42.2 Total weight of coke 57.8 100.0 206 ECONOMICAL GEOLOGY OF ILLINOIS. ANALYSIS. Moisture 9.0 Volatile matter 33 .2 Carbon in coke 52.8 Ashes (gray) 5.0 100.0 Carbon in the coal 52.2 Cannel Coal in same Seam. Thickness of the bed from eight inches to one foot; overlaid with black slate; underlaid with four feet of bituminous coal. No analysis of this coal has yet been made, but, judg- ing from its texture and general appearance, it does not differ from the Wataga cannel coal. The coal is dull, hard, compact; fracture slightly conchoidal; layers thick; con- tains bright, yellow, vertical plates of sulphuret of iron. NOTE. While engaged, during the past spring, in examining the coal deposits of Rock Island, I was induced to extend my examinations into Henry county, in part to confirm observations previously made in adjoining territory, and partly to satisfy myself as to the general development of our workable coal seams along the northwestern confines of the Illinois coal field. Commencing at the northwest corner of the county, coal No. 1 of the Illinois River sec- tion is opened and worked at various points in the bluffs of Rock and Green rivers, as at Cleveland and near Colona, as shown by Mr. Shaw, in the sections given on the preceding pages, and it presents the same general characters here as at Carbon Cliff, Coal Valley and other points in Rock Island county. It is overlaid by a peculiar dark-gray siliceous limestone, and its accompanying band of flint or chert, that enables any one to identify it without difficulty. This seam is worked by the Messrs. Perry, at Briar Bluff, near Green river, in Henry county, by a tunnel driven into the hillside. The coal is somewhat variable in thickness, and is sometimes cut off altogether by what the miners term a "horse-back." About forty feet below the cbal the shaly limestones of the Hamilton group outcrop but a short distance to the northward of the mines. A curious phenomenon was observed at these mines, in a remarkable geode-like cavern, or pocket, occurring partly in the coal, and extending into the fire-clay beneath. The cavity was ovate in shape, and about ten feet long by five feet in width, and two or three feet in depth, and surrounded by a solid crust. The inclosed cavity was filled with water and gas, and when the pick broke through the crust an explosion followed like the firing of a blast. On breaking into the cavity it was found to be thickly set with magnificent crystals of dog-tooth calcite, from six to eighteen inches in length, the points all directed towards the center of the cavity, like the crystals on the inner surface of a geode. Unfortunately many of these fine crys- tals were broken up and destroyed in removing them, but a f e w were preserved, and I was fortunate in securing some of them for the State cabinet. On the southwest quarter of section 21. township 17, range 1, coal seam No. 2 has been opened near the top of the bluff and immediately under the bowlder-clay. The coal is eighteen inches thick, and is overlaid by four or five feet of clay shale, forming but a poor roof. This was the first exposure <.f No. 2 that we met with in Henry county. The coal was underlaid by a few feet of fire-clay and clay shale, and not sufficiently exposed to be accurately measured, which was followed by a bed of bluish-gray septaria two or three feet thick, exactly like that found below the Colchester coal in McDonough county. This coal appears to be from thirty-five to forty feet above coal No. 1 at this point. At the Mineral Creek mines I found coal No. 1 worked at a shaft sixty feet in depth, and sunk in the valley of a small creek, and about one hundred and fifty yards southeast of the shaft the same coal outcrops seventy-five feet above its level in the shaft. In a boring made at this point below the coal, they reported seven feet of fire-clay and forty feet of shales, partly blue and partly gray, with a streak of coal, from two to four inches thick, about half way to the bottom. Some layers of sandstone, and one or more thin bands of iron ore, were passed through towards the bottom of the boring. HENEY COUNTY. 207 At the Mauch Chunck mines, about six miles west of Geneseo, coal No. 1 is worked just above the level of the creek by tunneling into the hill along its outcrop. It is here much thinner than it usually occurs in this part of the county, being reported as varying in thickness from two feet to three feet six inches. No. 2 is found here outcropping about forty feet above No. 1. A tunnel has been run into it, and considerable coal taken out, though the seam is here only from twelve to fifteen inches in thickness. At Geneseo coal crops out along the little run on the west side of the town, and is worked by Mr. Maynard in a shaft sunk from a higher level near the outcrop. The beds passed through in this shaft give the following section : Feet. In. No. 1 Soil and drift clay 20 No. 2 Hard rock (probably limestone) 1 3 No. 3 Sandstone t 5 No. 4 Blue shale 3 No. 5 Coal 3 No. 6 Hard dark shale 6 No. 7 Hard rock (concretion ?) 4 No. 8 Clay shale, or fire-clay 1 3 No. 9 Blue shale 10 No. 10 Black shale 6 No. 11-Coal 3 8 This seam has a parting of dark shale of variable thickness, and I am inclined to regard it as No. 2, which is frequently separated by a shale parting. The coal is also a rather soft and light coal, more like No. 2 than any other, though it contains more pyrite here than is unsually found in it at more southern localities. At Atkinson a coal seam about three feet in thickness has been opened on the eastern borders of the town, where it lies about fifteen feet below the surface, and from this point in a southwesterly direction it outcrops along the bluffs of Spring creek for a distance of about seven miles. Mowbray, Weatherspoon, Welch, Morrow, Shearer and Torpenning's mines, are all on this outcrop. The coal averages about three feet in thickness, and has an excellent roof of hard, .black slaty shale, passing upward into a blue clay shale con- taining nodules of ironstone and blue limestone. Thereof shales are locally filled with Aviculopecten rectilaterarius and Productus muricatus. The nodules of limestone and clay ironstone contain Productus Prattenianus, Pleurotomaria percarinata, P. Montforti- am