The length of the Chicago piers is as follows:—­North pier, 3900 feet long, 24 feet wide; south pier, 1800 feet long, 24 feet wide; and they are placed 200 feet apart.

Harbors of this kind have been constructed at Chicago, Waukegan,
Kenosha, Racine, Milwaukee, Sheboygan, Manitoowoc, Michigan City, and
St. Joseph, on Lake Michigan; at Clinton River, on Lake St. Clair; at
Monroe, Sandusky, Huron, Vermilion, Black River, Cleveland, Grand River,
Ashtabula, Conneaut, Erie, Dunkirk, and Buffalo, on Lake Erie; at Oak
Orchard, Genesee River, Sodus Bay, Oswego, and Ogdensburg, on Lake
Ontario.

For Lakes Huron and Superior it is believed that no appropriations have been made, the scanty population of their shores not seeming as yet to demand it, and those two lakes having in their numerous groups of islands more natural shelter for vessels than Michigan or Erie.

Besides these river-harbors, Col.  Graham recommends to Government the construction at certain points on the lakes of sheltered roadsteads, or harbors of refuge, to which vessels may run for shelter in bad weather, when it may be difficult or dangerous to enter the river-mouths.  These are proposed to be made by building breakwaters of crib-work, loaded with stone, and extending along the shore in a sufficient depth of water to admit vessels riding easily at anchor under their lee.  Many lives and much property would undoubtedly be saved every year by such constructions; for it is a difficult matter for a vessel to enter these narrow rivers in a heavy gale of wind, and if she misses the entrance, she is very likely to go ashore.

Another very important work to the navigation of the lakes is the deepening of the channel in Lake St. Clair.

Between Lakes Huron and Erie lies Lake St. Clair, a shallow sheet of water, some twenty miles in length, through which all the trade of the Upper Lakes is obliged to pass.  At the mouth of the river which connects this lake with Huron, there is a delta of mud flats, with numerous channels, which in their deepest parts have not more than ten feet of water, and would be utterly impassable, were not the bottom of a soft and yielding mud, which permits the passage of vessels through it, under the impulse of steam or a strong wind.

Mr. James L. Barton, a gentleman long connected with the lake-commerce, thus wrote some years ago upon this subject to the Hon. Robert McClelland, then chairman of the House Committee on Commerce:—­

“These difficulties are vastly increased from the almost impassable condition of the flats in Lake St. Clair.  Here steamboats and vessels are daily compelled in all weather to lie fast aground, and shift their cargoes, passengers, and luggage into lighters, exposing life, health, and property to great hazard, and then by extraordinary heaving and hauling are enabled to get over.  Indeed, so bad has this passage become, that one of the largest steamboats, after