THEORY. 185 



be strange, therefore, that shells might have existed formerly in the gravel, but are now 

 decomposed. There is a consideration, however, that leads us to suppose that shells 

 never existed in these beaches, although the ocean was washing the shores. The ice which 

 rendered the drift period too cold for life, had not yet disappeared. The icebergs, on 

 account of their greater bulk beneath the surface of the water, could not approach very 

 near the beaches, while they may still have floated in the Champlain and Connecticut 

 valleys, and have produced the third and most recent sets of striae, parallel with the 

 courses of these valleys. Wherever they approached so near the beaches as to be stranded, 

 materials were piled upon and about them, which, now that the ice is gone, appear as 

 conical and tortuous hills, intermingled with similar depressions which have been 

 described as moraine terraces. Hence we see that the ice might be so abundant, even in 

 the beach period, as to form an arctic climate ; so that very few, if any, forms of life 

 existed. 



It may be proper to state here, that no one of the Geological corps ever searched much 

 for fossils in these beaches, in Vermont. And as they are generally upon high hills, 

 very few excavations have ever been made in them, for any purpose. It would not be 

 strange, therefore, if in future investigations such remains should be found, as they have 

 already been in the drift upon Long Island and in Europe. 



7. We ascribe to this period other forms of Surface Geology, particularly the higher 

 Sea Bottoms, Submarine Ridges, Osars and Escars. These would be forming at the 

 bottom of the ocean whose shores were the beaches already described. The beach period 

 continued till terraces began to form, generally till the continent was not as high as it is 

 now by from 1000 or 1400 feet ; or until terraces began to be produced instead of beaches. 

 Still, some of the lower beaches would have been formed in the terrace period, as a few 

 of the higher terraces would have been deposited in the latter part of the beach period. 

 There was no definite line of demarkation between the two periods. 



8. During the beach period, therefore, but a small portion of Vermont was elevated 

 above the waters. The range of the Green Mountains, most of the north-east part of jthe 

 State, and every foot of land that is elevated say 1200 feet above the ocean, then appeared like 

 so many islands. As the elevation was gradual, every inch of surface was exposed to the 

 washing of water, although beaches did not form everywhere, just as now on the sea coast 

 there are alternations of rocks and sandy shores. 



THE TERKACE PERIOD. 



We have already stated the universal position of terraces lying above all forms of 

 drift and therefore concluded that in general local barriers for the separate basins did 

 not exist. We will now state a few principles respecting their position, modes of 

 occurrence, etc. 



1. The highest distinct terraces upon the different rivers, so far as we have measured 

 them, are as follows : On Connecticut River, at Bellows Falls, 226 feet ; at North Vernon, 

 237 feet; on Hoosac River, in Pownal, 307 feet ; on the Battenkill,atwest Arlington, 349 

 feet; on Winooski River, in Essex, from 240 to 260 feet above Lake Champlain; in Hines- 

 burg, 300 feet; on La Moille River, in Georgia, 132 feet; in Johnson, 190 feet; in Hardwick, 

 380 feet ; and on Lake Memphremagog, in Salem, 276 feet. Many others may be found in 

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