The history of Columbia County, Wisconsin, containing an account of its settlement, growth, development and resources; an extensive and minute sketch of its cities, towns and villages--their improvements, industries, manufactories, churches, schools and societies; its war record, biographical sketches, portraits of prominent men and early settlers; the whole preceded by a history of Wisconsin, statistics of the state, and an abstract of its laws and constitution and of the constitution of the United States
Chamberlin, T. C.
Topography and geology, pp. -120 PDF (5.3 MB)
TOPOGRAPHY AND GEOLOGY. river valley is even more noticeable, since it lies along the trend of the underlying strata, and was in large measure plowed out of a soft stratum by glacial action. Where it crosses the water- shed, near Horicon marsh, it presents the same general features that are seen at other points, and in an almost equally conspicuous degree. Except in the southern part of the state, this valley is confined on the east by an abrupt ascent, and, at many points, by a precipitous, rocky acclivity, known as "The Ledge "-which is the projecting edge of the strata of the Niagara limestone. On the watershed referred to-between the St. Lawrence and Mississippi basins- this ledge is as conspicuous and continuous as at other points, so,.that we have here again the phenomenon of a valley formed by excavation, running up over an elevation of 300 feet, and connecting two great systems of drainage. On the east side of this valley, as already indicated, there is a sharp ascent of 20o feet, on an average, from the crest of which the surface slopesgently down to Lake Michigan. The uniformity of this slope is broken by an extended line of drift hills, lying obliquely along it and extending from Kewaunee county soilthward to the Illinois line and known as the Kettle range. A less conspicuous range of similar chara'cter branches off from this in the northwest Corner of Walworth county and passes across the Rock river valley, where it curves northward, passing west of Madison, crossing the great bend in the Wisconsin river, and bearing northeastward into Oconto county, where it swings round to the westward and crosses the northern part of the state. As a general topographical feature it is not conspicuous and is rather to be conceived as a peculiar chain of drift hills winding over the surface of the state, merely interrupting in some degree the regularity of its slopes There will be occasion to return to this feature in our discussion of the drift. It will be observed that the southeastward slope is interrupted by valleys running across it, rudely parallel to Lake Michigan, and directing its drainage northward and southward, instead of directing it down the slope into the lake. The Mississippi slope presents several conspicuous ridges and valleys, but their trend is toward the great river' and they are all due, essentially, to the erosion of:the streams that channel the slope. One of these ridges constitutes the divide south of the Wisconsin river, already referred to. Another of these, conspicuous by reason of its narrowness and sharpness, lies between the Kickapoo and the Mississippi, and extends through Crawford, Vernon and Monroe counties. Still another is formed by the quartzite ranges of Sauk county and others of less prominence give a highly diversified chaiacter to the slope. Scattered over the surface of the state are prominent hills, some swelling upward into rounded domes, some rising symmetrically into conical peaks, some ascending precipitously into castel- lated towers, and some reaching prominence without regard to beauty of form or convenience of description. A part of these hills were formed by the removal by erosion of the surroundin strata, and a part by-the eaping up of drift material by the glacial forces. In the former case, they are compo'sd-ef rock; in the latter, of clay, sand, gravel and bowlders. The two forms are often combined. The highest peak in the southwestern part of the state is the West Blue mound, which is i,I5P feet above Lake Michigan; in the eastern part, Lapham's peak, 824 feet, and in the central part, Rib hill, 1263 feet. The crest of Penokee range in the northern part of the state rises i,ooo feet, and upwards, above Lake Michigan. The drainage systems correspond in general to these topograpical features, though several minor eccentricities are to be observed. The streams of the Lake Superior system plunge rapidly down their steep slopes, forming numerous falls, some of them possessing great beauty, prominent among which are those of the Montreal river. On the southern slope, the rivers, in the upper portion of their courses, likewise descend rapidly, though less so, producing a succession of' rapids and cascades, and an occasional cataract. In the lower part of their courses, the liii
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