The way being thus prepared for our entry into Lake Superior, it was decided to proceed the next day. Before leaving this point, it may be observed that the falls are produced by a stratum of red sandstone rock, which crosses the bed of the St. Mary's at this place. The last calcareous formation, seen in ascending the straits, is at Isle a la Crosse. As we proceed north, the erratic block stratum becomes heavier, and abraded masses of the granite, trap, sandstone, and hornblende series are confusedly piled together on the lake shores, and are abundant at the foot of these falls. In the central or middle channel, the waters leap from a moderate height, from stratum to stratum, at two or three points, producing the appearance, when seen from below, of a mass of tumbling waves. The French word _Sault_ (pronounced _so_) accurately expresses this kind of pitching rapids or falls. The Indians call it Bawateeg, or Pawateeg, when speaking of the phenomenon, and Bawating or Pawating, when referring to the place. Paugwa is an expression denoting shallow water on rocks. The inflection _eeg_ is an animate plural. _Ing_ is the local terminal form of nouns. In the south or American channel, there is no positive leap of the water, but an intensely swift current, which is parted by violent jets, between rocks, still permitting canoes, skilfully guided, to descend, and empty boats to be drawn up. But these falls are a complete check to ship navigation. The descent of water has been stated by Colonel Gratiot, of the United States Engineers, at twenty-two feet ten inches.[40] They resemble a bank of rolling foam, and with their drapery of trees on either shore, and the mountains of Lake Superior in the distance, and the moving canoes of fishing Indians in the foreground, present a most animated and picturesque view. [40] ST. MARY'S CANAL.--Thirty-three years have produced an astonishing progress. A ship-canal is now (1853) in the process of being constructed at these falls, by the State of Michigan, under a grant of public land for that purpose, from Congress. It is to consist of two locks of equal lift, dividing the aggregate fall. This canal will add the basin of Lake Superior to the line of lake navigation. It will enable ships and steamers to enter the St. Louis River of Fond du Lac, and to reach a point in latitude corresponding to Independence, on the Missouri. No other point of the lake chain reaches so far by some hundreds of miles towards the Rocky Mountains; and this canal will eventually be the outlet to the Atlantic cities of the copper and other mines of Lake Superior, and of the agricultural and mineral products of all the higher States of the Upper Mississippi and of the Missouri, and a part of Oregon and Washington on the Pacific.