Detroit River, a strait connecting Lakes St. Clair and Erie, and separating Canada from Michigan, about 22 m. long, and varying in breadth from 3 m. to less than 1/2 m. Its course from Lake St. Clair to just below Detroit is S. W., from which point it flows nearly due S. The total descent is about 2 ft. The river rises and falls with the level of the lakes it connects; the average annual variation is only about 1 1/2 ft., and the extreme variation, from February, 1819, when it was the lowest, to July, 1838, when it was the highest ever known, was only about 8 ft. The principal island is Grosse Isle, near Lake Erie; there are several smaller ones, which are used as fishing stations, from which large quantities of white fish are caught. Riviere aux Canards, near Maiden on the Canadian side, and the river Rouge near Detroit, small streams, are the principal affluents. As it has great depth of water and a strong and uniform current, the navigation of the Detroit is not affected by obstructions. The Canadian shore rises abruptly from the water to a height of from 20 to 25 ft., while the American shore is low, and in some places marshy.