284 GEOLOGY. 



Green Mountains they are found at the height of 6000 

 feet. 



395. Champlain Epoch. As the land elevated in the 

 Glacial epoch subsided, and water rose over it, the 

 Champlain epoch was ushered in. It found a vast quan- 

 tity of material which had been broken up by the ice of 

 glaciers and icebergs, and transported by them from the 

 sources from which it was obtained, mostly in southern 

 directions, and to greater or less distances. The finer 

 portions of this, the gravel, and sand, and mud, the mov- 

 ing waters of this epoch carried about and laid down in 

 widely-extended strata. These formations are alluvial, 

 the term being derived from the Latin word alluo, to 

 wash. Boulders never are found lying upon these beds, 

 for they were scattered by the glaciers and icebergs be- 

 fore these strata were laid down. They are often envel- 

 oped and covered up by the strata. They are often also 

 found on elevations in the neighborhood of Champlain 

 strata. In such cases there may have been once some of 

 the finer material of the drift mingled with them, and this 

 may have been washed away, the water not being able to 

 remove the boulders themselves. As the land subsided or 

 sunk down extensively in this epoch, some of the deposits 

 occurred on very high elevations. Hitchcock mentions 

 beaches of these deposits at great heights in the Green 

 and the White Mountains, one at the Franconia Notch 

 being 2665 feet above the level of the sea. The subsi- 

 dence of the land at the north during this epoch, lessen- 

 ing the amount of it above the surface of the water, and 

 so removing the arctic cold, which the raising of the, land 

 in the Glacial period had produced ( 391), melted, of 

 course, the glaciers of the temperate regions. This cre- 

 ated at the outset of this epoch a great flow of waters 

 over the continents, which carried with them large quan- 

 tities of the smaller materials of the drift. The deposi- 

 tion of these was much modified by the lakes and rivers 

 which already existed, and, in return, also made many 



