There have been, doubtless, during the epochs anterior to the Quaternary period many deluges such as we are considering. Mountains and chains of mountains were formed by upheaval of the crust into ridges, where it was too elastic or too thick to be fractured. Each of these subterranean commotions would be provocative of momentary irruptions of the waves. But the visible testimony to this phenomenon--the living proofs of this denudation, of this tearing away of the soil--is found nowhere so strikingly as in the beds superimposed, far and near, upon the Tertiary formations, and which bear the geological name of _diluvium_. This term was long employed to designate what is now better known as the “bowlder” formation, a glacial deposit which is abundant in Europe north of the 50th, and in America north of the 40th, parallel, and reappearing again in the Southern Hemisphere; but altogether absent in tropical regions. It consists of sand and clay, sometimes stratified, mixed with rounded and angular fragments of rock, generally derived from the same district; and their origin has generally been ascribed to a series of diluvial waves raised by hurricanes, earthquakes, or the sudden upheaval of land from the bed of the sea, which had swept over continents, carrying with them vast masses of mud and heavy stones, and forcing these stones over rocky surfaces so as to polish and impress them with furrows and striæ. Other circumstances occurred, however, to establish a connection between this formation and the glacial drift. The size and number of the erratic blocks increase as we travel toward the Arctic regions; some intimate association exists, therefore, between this formation and the accumulations of ice and snow which characterize the approaching glacial period. There is very distinct evidence of two successive deluges in our hemisphere during the Quaternary epoch. The two may be distinguished as the _European Deluge_ and the _Asiatic_. The two European deluges occurred prior to the appearance of man; the Asiatic deluge happened after that event; and the human race, then in the early days of its existence, certainly suffered from this cataclysm. The first occurred in the north of Europe, where it was produced by the upheaval of the mountains of Norway. Commencing in Scandinavia, the wave spread and carried its ravages into those regions which now constitute Sweden, Norway, European Russia, and the north of Germany, sweeping before it all the loose soil on the surface, and covering the whole of Scandinavia--all the plains and valleys of Northern Europe--with a mantle of transported soil. As the regions in the midst of which this great mountainous upheaval occurred--as the seas surrounding these vast spaces were partly frozen and covered with ice, from their elevation and neighborhood to the pole--the wave which swept these countries carried along with it enormous masses of ice.