Box 15, Folder 8: Geological Survey, Draft Report 1874

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XV Drift.

Under this head we may include all those deposits of clay, sand, gravel and boulders that are spread out uncon-formably upon all the before mentioned rocks. They cover Equally the newest and the oldest of the series and are therefore the last results of that long - continued series ^succession of events that were instrumental in producing that part of our great continent included in Wisconsin.

Evidence derived from the Existence, in other countries of Extended series of rocks between the Devonian and the Drift, shows that an immensely long interval of time was interposed, during all of which, Wisconsin was dry land - subject to the abrading influences of rains and frosts.

Drift shows itself in three distinct forms : 1st A hardpan or unstratified boulder clay, resting directly upon the smoothed and striated rock- surface, very hard and tough, and destitute of fossils. This is the original deposit ^under the great glacier, a thousand feet or more in depth, which once crept slowly but surely over the surface: - 2d Beds of sand and gravel separated from the hardpan by the action of running

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Water after the glaciers began to melt away: and 3d Beds of fine clay also separated from the hardpan at the same time, but deposited in the comparatively still water of the numerous great lakes that ^then Existed. This action of rivers and lakes in assorting the materials of the Drift is continued, though upon a much smaller scale, to the present day.

The hardpan affords firm banks for our lakes, and is the dread of well = diggers; the gravel and sand are useful in road-making and for mortar; and the clay=beds afford the material for our white or Cream - colored brick.

After this glacial period, when the ice had retired, vegetation was spread over the land, and animals of various kinds began to appear. Among these were some now Entirely Extinct, including the fossil Elephant (mammoth) and the mastodon. During this time trunks of trees became buried in the new deposits now often dug up from wells +c The great amount of rain= fall filled the valleys with large rivers carrying away the looser materials on the surface but leaving the heavier boulders perched upon the surface, as if they had been dropped from an iceberg.

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These strong currents probably were the means of forming many of the ridges and hillocks that now diversify the surface of the ground.

It is now impossible to know what was the condition of the surface of the state and what were the plants and animals, just previous to this glacial Epoch, for all traces of them were Effaced by the rasping and grinding Effects of the moving ice.

Valleys were filled up and hills cut down; great basins were scooped out to form the beds of the future lakes.

When the ice was withdrawn to whole surface was covered with drift.

It still remains to be accounted for that in the lead = region in this state there is almost a total absence of the Drift phenomena.

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Pre Historic Man in Wisconsin.

A race of people once occupied our soil of whom very little is known Except what can be gathered from their works and a few fragments of their skeletons. With his introduction geological history properly Ends; and it becomes important to know whether he was, or not, Cotemporary with the mammoth and mastodon.

The indications now are that they were quite different in many respects from the modern Indians, though these may be their descendants. In habits they were similar to other savage peoples - using the bow, and ^an arrow tipped with flint, to secure their game or punish their Enemies.

He made use of native copper (which he brought from Lake Superior, or found in the glacial drift) in making his arrow heads, knives, chisels, axes +c though it is doubtful whether he had the skill to mould this metal into form. His implements of unpolished stone and of hammered copper, and now found buried many feet in the Earth; thus indicating the lapse of many ages since his time.

But perhaps the most striking peculiarity of the pre= historic man of

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of Wisconsin, was his habit of throwing up mounds of Earth in the form of animals and of man. For what purpose these were Erected can now, of course, be only an object of conjecture. That they had some significance seems quite Evident.

We here give a carefully prepared figure of this pre= historic man and one of the animals as represented in the mounds. They Each have a total length of one hundred and twenty five feet; the former, in Sauk County, was surveyed by Mr. Wm H. Canfield; the latter near Cassville Grant County surveyed by Mr. Moses Strong.

Milwaukee, July, 1874

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