A Mystery of the Lake
Somebody has been examining the mystery of our inland seas, and comes to the following conclusion concerning them and the little fishes:
Lake Erie is only 60 or 70 feet deep; but Lake Ontario, which is 592 feet deep, is 230 feet below the tide level of the ocean, or as low as most parts of the Gulf of St. Lawrence; and the bottom of lakes Huron, Michigan and Superior, although the surface is so much higher, are all, from their vast depths, on a level with the bottom of Ontario. Now, as the discharge through the river Detroit, after allowing for the probable portion carried off by evaporation, does not appear by any means equal to the amount of water which the three upper lakes receive, it has been conjectured that the subterranean river may run from Lake Superior, by the Huron, to Lake Ontario.
Thus conjecture is by no means improbable, and accounts for the singular fact that salmon and herring are caught in all the lakes communicating with the St. Lawrence, but in no others. As the falls of Niagara must have always existed, it would puzzle the naturalists to say how these fish get into the upper lakes, without some such subterranean river; moreover, any periodical obstruction of the river would furnish a not improbable solution of the mysterious flux and reflux of the lakes.