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"His character was one upon which his friends can look from any point of view with pride, with satisfaction and with love. To a mind trained by years of study and filled with valuable learning, he added a character of great moral excellence and of unsullied honor.

"Sir Knight Strong was initiated, passed and raised to the Sublime Degree of Master Mason in Mineral Point Lodge, No. 1; became a Royal Arch Mason in Iowa Chapter, No. 6, in Mineral Point, and was received and constituted a Knight Templar in Mineral Point Commandery, No. 12; receiving all his degrees in the place of his birth, and the home of his lifetime, and at the hands of those who knew full well that the honors he received were most worthily bestowed. His brethren mourn his loss with grieving and heartfelt sorrow. Such men as he it is who honor Masonry in their lives, and dying leave upon it the luster of a pure life and unspotted character."

THE DRIFTLESS AREA.

Again resuming the narrative of geologic fact, it is observed that the most interesting fact presented for the consideration of the general geologist, is the entire absence of "drift," or diluvium throughout the southwestern quarter of the State, and, while extending far to the north, still including the region referred to herein. The lead district is driftless. About twelve thousand square miles are embraced in these boundaries. The investigations by Mr. Roland D. Irving and Mr. Moses Strong have resulted in much interesting information. From the official reports is quoted the following:

"In the driftless region, which occupies nearly one-fourth of the entire area of the State, the drift is not merely insignificant, but absolutely wanting. Except in the valleys of the largest streams, like the Wisconsin and Mississippi, not a single erratic bowlder, nor even a rounded stone, is to be seen throughout the district; whilst the exception named is not really an exception, the small gravel deposits that occur on these streams having evidently been brought by the rivers themselves, during their former greatly expanded condition, from those portions of their courses that lie within the drift-bearing regions."

Those readers of this work who have not easy access to the official reports, may be interested to know the boundaries of the driftless region, and it is, therefore, here stated. The outline is, for the most part, sharply defined, both by a more or less sudden cessation of the drift materials, and by a change in the topography, as the line is crossed, from one side to the other. This is more especially true of the eastern boundary, in which the reader is naturally most interested. On this line are often seen heavy morainic heaps-that is, deposits of such bowlders and gravel as scientists have decided are carried under, or attached to the sides of glaciers, or to the center of glaciers which are formed by the union of two separate bodies of that nature. effects of purely subaerial (or open air) erosion without drift, and the effects of glacial erosion with drift, are plainly distinguishable along these lines. The northern boundary of the region is mainly level country, the drift materials gradually diminishing to the south.

The

Mr. Strong defines the eastern line through Green County as beginning at the southwest corner, and waving irregularly northeast, until it crosses the county line on the north, about fifteen miles from the east line of Iowa County. Thence the line curves to the west, and crosses the Wisconsin about three miles east of the northeast corner of Iowa County; thence, due north to Baraboo, curving as it crosses the Sauk County north line to touch Range 5; thence, with a gradual curve, it includes nearly all of Adams County, and swings to the northwest, touching Grand Rapids as its northeastern point; thence, mainly west to the Mississippi River. This is now the accepted area, although Mr. Whitney differs somewhat from the definition as to the line through Adams and Juneau Counties. The report of 1877, by Mr. Irving, is referred to, for the benefit of those who desire a more detailed and argumentative description.

Mr. Irving says: "The nature of the topography of the driftless area, everywhere most patently the result of subaerial erosion exclusively, is even more striking proof that it has never been invaded by the glacial forces than is the absence of drift material. Except in the level country of Adams, Juneau, and the eastern part of Jackson County, it is everywhere a region of narrow, ramifying valleys and narrow, steep-sided dividing ridges, whose direction are toward

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every point of the compass, and whose perfectly coinciding horizontal strata prove conclusively their erosive action. Each one of the numerous streams has its own ravine, and the ravines are all in direct proportion to the relative sizes of the streams in them." [Reference is made to the contour maps drawn by Mr. Strong, displaying, with instructive plainness, the topographic phenomena of the region.]

"The altitude of the driftless area, as compared with the drift bearing regions, becomes a matter of some importance in any attempt to explain the absence of the drift phenomena. It has been stated by some writers that the driftless area is higher than the drift-bearing, and was, consequently, not subjected to glacial invasion. It is true that in general the eastern half of the State is lower than the western, but from what follows it will be seen that farther than this the statement is inaccurate. From the south line of the State, as far north as the head of Sugar River, in Cross Plains, the county west of the drift limit rises rapidly from 200 to 400 feet. Just north of the head of Sugar River the limit crosses high ground-the western extension of the high limestone and prairie belt of northern Dane and southern Columbia Counties--and the altitudes east of the limit are as great as those to the west; whilst in passing from the head of the Catfish River westward, a glacier must have made an abrupt ascent of fully 300 feet. North of Black Earth River the limit has the higher ground, by 200 feet, on the east. Sauk Prairie is crossed on a level, and though higher ground occurs west of the prairie, its topography and the absence of drift show that the glacier never reached so far. Where the quartzite range north of Sauk Prairie is crossed by the limit, it is higher (850 feet above Lake Michigan) than any part of the driftless area except the Blue Mounds, whilst only a few miles east a great development of bowlders and gravel is found on one of the highest portions of the range (900 to 950 feet altitude). From the Baraboo north to the Sauk County line, there appears to be in relation between the position of the limit and the altitude of the country. From the north line. of Sauk County, in curving to the eastward and northward around Adams County, the limit is on the very crest of the divide. From its position near the middle of the east line of Adams County, the country, for forty miles to the west, is from 100 to 200 feet lower. From the northwest part of Adams County to the Wisconsin River the limit is in a level country; whilst from the Wisconsin westward, the country north of it is everywhere much higher than that to the south, the rise northward continuing to within thirty miles of Lake Superior."

In his discussion of the glacial drift, Mr. Irving reaches certain conclusions, which are here reproduced only so far as they relate positively to the area devoid of drift. The negative arguments, or those that go to prove the absence of drift, because the region is not like the vast majority of the country, and of the Northern Hemisphere of the globe, are recited in brief:

"1. The drift of Central Wisconsin is true glacier drift. [See Report 1877, p. 630.]

2. The Kettle Range of Central Wisconsin is a continuous terminal and lateral moraine. The mere fact of the existence of such a distinct and continuous belt of unstratified and moraine-like drift, which, in much of its course, lies along the edge of the driftless area, or, in other words, along the line on which the western foot of a glacier must long have stood, would go far toward proving the truth of the proposition [that this is true glacial drift], of which, however, a complete demonstration is at hand. In all the country just inside the Kettle Range, we find that glacial striæ-channels-lines of glacial erosion, and lines of travel of erraticsbowlders, or minerals foreign to the locality where found-preserve a position at right angles to the course of the range, although that course veers in the southern part of the district from west to north. East of the Central Wisconsin district, the Kettle Range extends eastward and northeastward to the dividing ridge between the valley of Lake Michigan and the valley in which lie Green Bay, Lake Winnebago, and the head-waters of Rock River, and along this ridge northward, into Green Bay Peninsula. All along this part of its course, Prof. Chamberlin has found the glacial striæ pointing east of south, and toward the Kettle Range, whilst along the middle of the Green Bay Valley he finds the striæ directions parallel to the main axis of the valley, or a little west of south. On the west side of this great valley, and along the eastern border of the Central Wisconsin district, the striæ trend about southwest, whilst still

further west, they gradually trend further to the west, becoming at last nearly due west, or at right angles to the western Kettle Range.

"We have then a most beautiful proof that at one time the Green Bay Valley was occupied by a glacier, which was not merely a part of a universal ice sheet, but a distinctly separate tongue from the great northern mass. The end of this glacier was long in northern Rock County, its eastern foot on the East Wisconsin divide, and its western on the summit of the divide between the Fox and Wisconsin River systems, as far south as southern Adams County, after which it crossed into the valley of the Wisconsin, and from that into the head-waters of the Catfish branch of Rock River, in the Dane County region. Whilst the main movement of the glacier coincides in direction with the valley which it followed, it spread out on both sides in fan shape, creating immense lateral moraines. Peculiar circumstances caused the restriction of the eastern moraine or narrow area, whilst that on the west, having no such restriction, spread out over a considerable width of country, the breadth of the moraine reaching in Waushara County as far as twentyfive miles. This width of moraine must have been due to the alternate advance and retreat of the glacier foot. Such an advance and retreat appears, moreover, to be recorded in the long lines of narrow sinuous ridges, each marking, perhaps, the position of the glacier foot, or a portion of it, during a certain length of time. The intersecting of these winding ridges, which have no parallelism at all with one another, appears to me to have been the main cause of the formation of the kettle depressions. Col. Whittlesey [Smithsonian Contributions to Knowledge], has supposed that these owe their origin to the melting of ice masses included within the moraine materials, and this may possibly be true with regard to more regularly circular kettles. The thickness of the great glacier we can only conjecture. It is easy to see, however, that it was at least a thousand feet, for it was able to accommodate itself to variations in altitude of many hundred feet. Morainic drift occurs on the summit of the Baraboo ranges over 900 feet above Lake Michigan, and on the immediately adjacent low ground, 700 below.

"3. The driftless region of Wisconsin owes its existence, not to superior altitude, but to the fact the glaciers were deflected from it by the influence of the valleys of Green Bay and Lake Superior. Some writers have thrown out the idea that the driftless area is one of present great altitude compared with the regions around it, and that, by virtue of this altitude during the Glacial period, it caused a splitting of the general ice sheet, itself escaping glaciation. This idea may have arisen from the fact that, in the southern part of the area, the district known as the lead region,' has a considerable elevation; but the facts hitherto given have shown that, in reality, the driftless area is for the most part lower than the drift-covered country immediately around; the greatest development, for instance, of the western lateral moraine of the glacier of the Green Bay Valley, having been on the very crown of the water-shed between the Lake Michgan and Mississippi River slopes, whilst the driftless region is altogether on the last-named slope. Moreover, to the north, toward Lake Superior, and in Minnesota, the whole country covered with drift materials lies at a much greater altitude. J. D. Whitney, in his report on the lead region of Wisconsin, favors the idea that the driftless district stood, during the glacial times, at a much greater relative altitude than now, and so escaped glaciation. But it is evident that, in order that this could have been the case, either (1) a break or bend in the strata must have taken place along the line of junction between driftless or drift-bearing regions, or else (2) the driftless region has since received relatively a much greater amount of denudation than the driftbearing.

That

That no break or bend ever took place along the line indicated, is abundantly proven by the present perfect continuity of the strata on both sides of the line, the whole region in Central Wisconsin being in fact one in which faults of any kind are things absolutely unknown. no sensible denudation has taken place in Wisconsin since the glacial times, in either drift-bearing or driftless areas, is well proven by the intimate connection with one another of the systems of erosion of the two regions. The valley of Sugar River, for instance, with its branches, is throughout its course worn deeply into the underlying rocks; on its east side it contains moraine drift, proving that it was worn out before the Glacial period, whilst on the west it

extends into the driftless regions. We are thus compelled to believe that, during the Glacial period, the region destitute of drift had the same altitude relatively to the surrounding country as at present. Before the Glacial period, portions of the drift-bearing region may indeed have been somewhat higher, for in it a considerable amount of material must have been removed from one place to another by the glacial forces. The only satisfactory explanation remaining, then, for the existence of the driftless region, is the one I have proposed. We have already seen that the extent of this region to the eastward was marked out by the western foot of the glacier which followed the valley of Green Bay. That it was not invaded from the north, is evidently due to the fact that the glacier or glaciers of that region were deflected to the westward by the influence of the valley of Lake Superior. The details of the movement for this northern country have not been worked out, but it is well known that what is probably the most remarkable and best-preserved development of morainic drift in the United States, exists on the water-shed south of Lake Superior. Here the drift attains a very great thickness, and the kettle depressions and small lakes without outlet are even more numerous and characteristic than in other parts of the State. The water-shed proper lies some thirty or forty miles south of the lake, and 800 to 1,200 feet above it, but the morainic drift extends twenty-five to fifty miles further southward. On the east side of the State, the drift of Lake Superior merges with that of Central and Eastern Wisconsin, while west of the western moraine of the Green Bay glacier, it dies out somewhat gradually, until 125 to 150 miles south of the lake the drift limit is reached. Much of the country twenty-five to seventy-five miles north of the driftless region, though showing numerous erratics, is quite without any marked signs of glaciation, as, for instance, along the valley of the Wisconsin, from Grand Rapids north to Wausau. Further west, the drift extends more to the southward. The course of the Lake Superior glaciers conveyed them further and further southward as they moved westward.

"Future investigations will undoubtedly bring out a close connection between the structure of the Lake Superior Valley and the glacial movements south of it. Even the facts now at hand seem to point toward some interesting conclusions. Projecting from the south shore of Lake Superior, we find two great promontories, Keweenaw Point and the Bayfield Peninsula. Both of the projections have a course somewhat transverse to the general trend of the lake, bearing some thirty degrees south of west. Both have high central ridges or backbones, which rise 1,000 to 1,500 feet above the adjacent lake, and are made up of bedded igneous rocks, sandstones, and conglomerates of the copper series. Both of these ridges continue far westward on the mainland, having between them a valley, partly occupied by the lake, which is a true synclinal trough; the rocks of the two ridges dipping toward one another. North of the Bayfield Peninsula, and again south of Keweenaw Point, we find two other valleys running in from the lake shore in the same direction. In all probability each one of these valleys has given direction to a glacier tongue. An inspection of a good map of the northern part of Wisconsin, Minnesota and Michigan, will serve to show that the almost innumerable small lakes (which are far more numerous than are shown in the best maps) of these regions, are concentrated into three main groups, each group corresponding to a great development of morainic drift, and lying in the line of one of the three valleys just indicated. I suppose that each of the lake groups is a moraine of the glacier which occupied the valley in whose line it lies. The main ice-sheet coming from the north met, in the great trough of Lake Superior, over 2,000 feet in depth, an obstacle which it was never able to entirely overcome, and so reached southward in small tongues composed perhaps of only the upper portions of the ice. These tongues being deflected westward by the rock structure of the country, and having their force mainly spent on climbing over the watershed, left the region further south untouched. The eastern part of the Lake Superior trough is not nearly so deep as the western, and the divide between Lake Superior and the two lakes south of it, never attains any great altitude, so that here the ice mass, having at the same time perhaps a greater force on account of its nearness to the head of the ice movement on the Laurentian highlands of Canada, was able to extend southward on a large scale, producing the glaciers of the Green Bay Valley, and of Lake Michigan.

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Although quite crude in its details, I am convinced that the main points of the explanation thus offered for the existence of the driftless region in the northwest will prove to be correct. To obtain a full elucidation of the subject, much must be done in the way of investigation, not only in Wisconsin, but over all of Minnesota and the States south, in order that the details of the ice-movement for the whole northwest may be fully understood.

"4. The stratified drift of the valleys (in the drift-covered regions) owes its structure and distribution to the water of the swollen streams and lakes that marked the time of melting of the glaciers.

"5. The depth below the present surface of the rock valleys appears to indicate a greater altitude of this part of the continent during the Glacial period than at the present time."

TOPOGRAPHY AND SURFACE GEOLOGY OF THE LEAD REGION.

Mr. Moses Strong, in his report of 1877, says: "Unlike most regions which nature has selected for the reception of metallic ores and useful minerals, the lead region bears no evidence. of any sudden disturbances or violent action of physical forces. The effects produced by igneous and eruptive agencies are wanting. Faults and dislocations of strata are nowhere found. The only irregularities are slight upheavals or bending of the strata (and these never of great extent), producing changes of but a few feet from the normal dip. Between the geological condition and the general surface contour of the country, there is no direct correlation. The existence of a hill or a valley on the surface is not due to a subterranean elevation or depression of surface, as is by many supposed, and whatever irregularities exist must be chiefly attributed to the milder natural agencies now constantly at work, such as running water, frost, winds, etc., acting through an immensely long period of time.

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Drainage. The most marked and persistent feature of the lead region is the long dividing ridge, or water-shed, which, commencing near Madison, continues almost directly west to the Blue Mounds, a distance of about twenty miles. Here it takes a slight bend to the southwest for fifteen miles until it reaches Dodgeville, where it resumes its westerly course until it terminates in the bluffs at the confluence of the Wisconsin and Mississippi Rivers. Its total length is about eighty-five miles. Two points are noticeable-one is its general uniform directness of outline (it being subject to but few and unimportant flexures), and the other is its parallelism with Wisconsin River so long as the latter holds an approximately westerly course, the summit of the ridge being always about fifteen miles from the river. The divide maintains an average elevation of about six hundred feet above Lake Michigan, and is seldom less than five hundred or more than seven hundred, except at the Blue Mounds, where it gradually rises east and west for several miles until it attains an elevation at the west mound of one thousand one hundred and fifty-one feet. This, however, is an extreme case, and, in fact, the only marked exception to the general level. In the town of Mount Hope, a slight decrease of elevation is about four hundred and thirty feet at a point within a mile of both the Mississippi and Wisconsin Rivers. There are also two main branches or subdivisions of the water-shed. Of these, the western is the ridge which separates the waters that flow into the Platte and Fever Rivers from those which flow into the Pecatonica. It leaves the main divide in the town of Wingville, and, passing through the townships of Bellmont and Shullsburg in a southeasterly direction, passes out of the State in the town of Monticello. The ridge is not so conspicuous as the main watershed, either for the directness of its course or the uniformity of its elevation. The most conspicuous points on it are the Platte Mounds, which appear from a distance to be very high, but their height is only relative, their actual elevation being about seven hundred feet above Lake Michigan. The ridge appears to slope somewhat in its approach to Illinois, its average elevation there being about five hundred feet.

"The easterly subdivision is that which separates the waters of the Pecatonica and Sugar Rivers. It may be said to begin at the Blue Mounds or a couple of miles east of them, and, pursuing quite a devious course through the townships of Primrose, Washington and Monroe, it crosses the State line in the town of Jefferson. This ridge is characterized by a much greater

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