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Lake Michigan

Having completed the foregoing notices of the counties on Lake Michigan it seems proper here to make some observations relative to this lake. It is the only one of the great chain of inland seas that lies wholly within the limits of the United States. Its exact form and dimensions cannot be ascertained until the surveys of Wisconsin and Michigan are united at the north, and the meanders of that portion of the lake [there] are completed. It is estimated to have a length of about three hundred and twenty miles and a mean or average breadth of seventy miles, having therefore an area of twenty two thousand four hundred square miles. This is exclusive of Green Bay which may be considered as only a portion of this great lake having an area of about two thousand square miles. The surface of Lake Michigan is five hundred and seventy eight feet above the level of the ocean, and its mean depth

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