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[No. 11.]
Annual report of the state geologist.

Office of State GEOLOGIST,

Detroit, February 1, 1841. To the Senate and House of Representatives:

In conformity with instructions contained in the act authorizing a geological survey of the state, I have the honor to lay before you, an outline of the operations of the department over which I have been placed, together with the general progress towards completion of the whole work.

It is a matter of regret to me, that the sufferings and hardships to which I have been exposed in conducting the field work over the wilderness portions of our state, have so far impaired my health, as to render it impossible for me to enter into so minute details as had been anticipated. I regret this the more, since it leaves many wide spaces in portions of the present report, which are of much consequence to a proper understanding of the whole. But since the annual reports are intended to refer rather to the progress of the work than to its results, and since the whole will be embraced in a more perfect form hereafter, this defect is of less importance than it otherwise would be.

My individual labors, during the past season, have been chiefly devoted to surveys connected with the northern slope of the upper peninsula, and to this district, the chief observations in this report, will be directed.

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UPPER OR NORTHERN PENINSULA.

General description and Topographical features. The published maps of that portion of the state of Michigan usually known as the upper peninsula, are so defective, not only in details, but also in general outline, that the task of giving a description of any portion, in such a manner as to render it intelligible to any person who has not actually traveled over it, is exceedingly difficult

. The extent of these geographical inaccuracies is much greater than would at first be supposed, for scarcely a single feature of the interior is given as it actually exists; mere brooks are magnified to rivers, and again those streams justly deserving the name of rivers, are either wholly omitted or scarcely noted; while the courses of the streams, as laid down, are almost invariably as far from the truth as could be conceived. Nor do the inaccuracies stop here, for even the coast maps of the great lakes, by which our upper peninsula is in part surrounded, are usually so defective

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as scarcely to be recognized, except in their most general outlines. *

I have already, in a previous report, referred in general terms, to that portion of the upper peninsula bounded by lakes Huron and Michigan, for which reason my remarks at this time will be mostly confined to the northerly portion of the peninsula, or that portion bordering upon Lake Superior.

So little is known of the extent of country constituting the upper peninsula, that it may not be misplaced to make some reference to its dimensions, though at this time most of the estimates must be regarded as mere approximations. The most extreme length of the district is embraced between Point de Tour, of Lake Huron, on the east, and the mouth of Montreal river, of Lake Superior, on the west. From Point de Tour, the direction of the mouth of Montreal river is very nearly north, 80° 30' west, and the direct distance does not vary far from 316 miles. This estimate, it will be perceived, does not include Drummond's Island, which, if included, would add some 20 miles to the length as already given.

The easterly portion of the peninsula is narrow, and its width, for a distance of 130 miles west from Point de Tour, varies from 30 to 50 miles; west from this, the peninsula widens rapidly, though its width is exceedingly irregular. I am unable, at this time, to state with very much accuracy, extreme width of the upper peninsula, but the area of the whole may be estimated at very nearly two-thirds that of the lower, or southern peninsula.

The topography and general features of the upper and lower peninsulas differ so widely from each other, that, with the simple exception of a part of the easterly extremity of the upper peninsula, they scarcely admit of a comparison. The wide contrast exhibited by the two districts, is wholly dependent upon geological differences, and these are so strongly marked, that they could not fail to attract the notice of the most superficial observer. *** In the last report I had the honor to lay before you, some general references were made to the topography of the southern slope of the upper peninsula, which embraced simply those portions bordering upon lakes Huron and Michigan, and extending from Point de Tour to Menominee river.

Although the rocks of the district extending from Point de Tour to Chocolate river, upon the northerly or Iake Superior slope, belong to an older series than those lying south, and are different in composition, the general features of the two dis

* I am happy in being able to except from this otherwise universal charge of inaccuracy, the coast map of Lake Superior published by the society for the diffusion of useful knowledge. This map was reduced from the surveys of Capt. Bayfield, R. N., as returned to the British admiralty office, and so far as the British coast is concerned, the map

is minutely correct. The American coast upon this map is faithfully delineated in its general outline, but in mindtiæ it is frequently deficient. Vol. I.

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tricts, nevertheless, bear a close resemblance. Easterly from Point Iroquois, the country is for the most part flat, or but slightly elevated, and the near approach of the rock to the surface so far prevents the descent of the waters, as to give rise to extensive districts of wet and swaly land. Westerly from Point Iroquois to Chocolate river, the country is more elevated, and has a much smaller proportion of wet land. A range of hills, having an elevation varying from 300 to 600 feet above Lake Superior, commences a little easterly from Point Iroquois, and stretches very nearly west, or but a few degrees north of west, until the western escapement again appears upon the coast, giving rise to the elevated hills of which the Pictured rocks and Grand island form a part. The outline of this range of hills has the most perfect regularity, being unbroken and uniformly covered with a dense growth of timber.

West from Chocolate river, to our boundary line at Montreal river, the physical character of the country is widely different from that of the district before referred to.

This country is made up of a series of irregular, knobby ranges of hills, that have a general easterly and westerly direction, with intervening valleys of flat or gently rolling land. These hills not unfrequently rise to a height of from 600 to 900 feet, very near to the immediate coast of Lake Superior, and at a distance of 15 to 20 miles south from the coast, portions of some of the ranges rise to a height of 1,200 to 1,300 feet above the level of that lake. The ragged and broken outline which this district presents, when viewed in detail, from the lake, contrasts in a striking manner, with that of the country lying east from Chocolate river; for, instead of the regular and unbroken range of hills, uniformly covered with a dense forest, that occur in the latter district, we have a series of ranges of broken hills, with knobs not unfrequently nearly or quite destitute of timber. The escapements of these hills are sometimes so abrupt as to render them difficult of ascent.

The only exception to the general easterly and westerly direction of these ranges of hills, occurs in that range constituting the Porcupine mountains. These mountains rise somewhat abruptly almost upon the immediate coast of Lake Superior, at a point 37 miles north-easterly from the mouth of Montreal river, and from this point they stretch inland, in a direction which, for the first 30 miles, is very nearly south-south.west, after which their course is more westerly, and in the direction of the sources of the Wisconsin river. The most elevated points of the Porcupine mountains, near to Lake Superior, aitain an altitude of very nearly 950 feet, but several of the knobs, at a distance inland, rise from 1,000 to 1,300 feet above the level of the waters of that lake.

The valleys, before referred to as separating these ranges of hills, are uniformly heavily timbered, and by far the largest proportion of this timber is beech and maple.

• The length of the hilly or mountainous district, estimating in a direct line west from Chocolate river to the boundary line on Montreal river, is very nearly one hundred and sixty miles, and it does not probably extend, at any point, more than 20 to 25 miles south from this line. Estimating this hilly district to extend regularly 20 miles south of a line drawn from the points before mentioned, the greatest width of the district would be opposite Keweenaw point, which extends 67 miles north from this line, making the total width at this point 87 geographical miles. The very great irregularities of the coast, with the numerous deep bays and projecting points upon the north, together with the irregularities of the ranges of hills upon the south, cause so great variations in the width of the district, that it is impossible, with the present information upon this subject, to estimate the width of the district with any great degree of accuracy. Keweenaw bay, of Lake Superior stretches 60 miles, estimating from the extremity of Keweenaw point, into this hilly or mountainous country,

South from the range of hilly country alluded to, and extending to Green bay, the country at first becomes more level and finally flat, though with several regular and unbroken ranges of hills. In topography and general character, it more nearly resembles that district of country which lies east' from Chocolate river.

Of the district of country lying between the hilly country and Green bay, less is known than of any other portion of the upper peninsula. The extent of my duties did not permit me to extend my examinations very far into it, nor was I enabled to obtain any information as to its general character.

The streams which discharge their waters into Lake Superior upon its south shore, are invariably short, and with very few exceptions, the quantity of water they discharge is small. This remark, in fact, may apply to the whole of the region of country surrounding that lake, for this immense body of water is completely surrounded by hills that, at no great distance from the lake, fall away more or less rapidly. Thus, while many of the streams discharging their waters into Lake Michigan, Green bay and the Mississippi river, have their sources near to the south shore of Lake Superior, so also, many of those streams which discharge their waters northerly into Hudson's bay, have their sources near to the north coast of the lake. The near approach of the summit of the ranges of hills surrounding the lake, to the immediate coast, leaves the area of country draining into Lake Superior, comparatively small.

The most important of the streams entering Lake Superior upon

its south shore and within the limits of our state, (commencing near the foot of the lake and enumerating westwardly,) are the Tequoimenon, Train, Chocolate, Death, Yellow dog, Huron, Portage, Fire Steel, Ontonagon, Iron, Presque Isle, Black and Montreal rivers. Besides these, there are innumerable creeks, which are usually known to voyageurs as rivers, for this term is applied indiscriminately to all. The waters of most of these streams are remarkably transparent and pure, with brisk currents and numerous cascades, and they almost invariably contain an abundance of the brook trout, a circumstance which I mention, from the fact that this fish is scarcely known in the streams of the southern peninsula.

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The Tequoimenon river, which is the only stream east from Chocolate river, that in reality breaks through the range of sandstone hills, before mentioned as extending westerly from Point Iroquois, has its embouchure about 18 miles south from Whitefish point, and near the foot of the lake. The discharge is through loose sands, and there is an average of 4 to 41 feet water over the bar. Having passed the bar the water for a distance of 7 to 8 miles varies from 10 to 15 feet.

Some of the sources of this stream approach very nearly to Lake Michigan, being directly at the base of the range of lime rock hills, referred to in my third annual report.

The Tequoimenon river, with the exception of a distance of some four to five miles, while passing through the range

of sandstone hills before alluded to, is, through its whole course, a sluggish stream, though at many points having a strong, deep current. The character of the river, in its passage through the range of hills referred to, is totally changed, for it has there numerous chutes and falls, with alınost.continuous rapids. At one point, the whole body of water contained in the stream is precipitated by a single leap, from a height of forty-six feet

, and the effect of this fall is much heightened by the elevated and overhanging rocks that bound the river upon either side.

Most of the small streams, discharging into Lake Superior between the foot of the lake and Chocolate river, have their sources to the north of the elevated range of hills mentioned, or minor branches only descend from those hills.

Chocolate river, which discharges its waters into Lake Superior at a point 146 miles very nearly due west from the Saut de Ste Marie, is a stream of considerable magnitude, though in consequence of the loose sands at its mouth, it is difficult of entrance at ordinary stages of water, even with barges of mo

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