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Michael (St.) Island-See La Pointe.

Michigan (Lake), one of the largest of the great chain of Inland Seas, and the only one which lies wholly within the limits of the United States; about three hundred and twenty miles in length, and about seventy miles average breadth; having an area of twenty two thousand four hundred square miles; independent of Green Bay, which may be considered as only a portion of this great lake, and which is about one hundred miles long and twenty broad, having an area of about two thousand square miles. Its mean depth is supposed to be about one thousand feet, or 400 feet below ocean level. Its greatest width is between Milwaukee and the mouth of Grand River, in Michigan where it is supposed to be from ninety to one hundred miles. The western coast of Lake Michigan consists generally of a very steep bank of clay but slightly intermixed with gravel, rising from twenty to sixty or eighty feet above the water, sometimes based