Tradition says, that the falls of Niagara have, for a great length of time, been receding;—that they were originally situated at the foot of the rapids near Lewistown, a distance of seven miles from their present position.[34] This idea is no doubt correct. Masses of rock must, from time to time, have been shaken from the top and sides of the falls, by the continual abrasion of the rapids. It is to be presumed, that the falls will continue to move up towards Lake Erie; lessening the waters of the upper lakes, and increasing those of the lower, in proportion as the descent of the bed of the river above the present situation of the falls may be greater, and the obstructions in it less. In the course of many centuries, the falls will, probably, reach Lake Erie itself; in which case the upper lakes may be partially drained, and Lake Ontario be overflown. It has been asserted, that this lake fills once in seven years. As to the time, this must be a whim; but there is reason to believe that the lake occasionally fills, because its sources are numerous and great, its discharge is not very ample, and high north-east winds, which frequently prevail here, retard the {80} progress of the water towards the river St. Lawrence.
I may here more particularly notice Lake Ontario. Its length is about one hundred and seventy miles, and its breadth about sixty miles. It contains a great many islands, nearly all of which are situated at the easterly end of the lake. The principal islands are Amherst, Wolf, Gage, and Howe. The land on the north-east coast of this lake is low, and in some places marshy; near Lake Champlain, however, the country is somewhat mountainous.
