MORAINE TERRACES. 33 



they formerly emerged from the mountains, into what is rlow a valley with terraces, 

 but was then an estuary, or lake, or broad river. The materials, brought down 

 from the mountains by tbe tributaries, were pushed forward into these expansions 

 of water, and spread, in part at least, over the bottom. As the drainage went on, 

 these subaqueous deposits gradually emerged in the form of deltas, and were sub- 

 sequently cut through by the streams. The result would be, as I shall shortly 

 attempt to show, that a new set of lateral terraces would be formed in the delta 

 terraces. Hence at present, several of the sections of terraces that have been 

 described on the preceding pages, cross from one side of an eroded delta terrace to 

 the other. This is the case in No. 13, in which the right hand terraces were all 

 formed upon a delta terrace of Deerfield river. The same is true of the left hand 

 portion of No. 25, which crosses the Ashuelot river in Hinsdale, New Hampshire, 

 as also of No. 28 in Brattleborough, which crosses the original delta terraces of 

 West river and Whetstone brook. On Deerfield river, in Charlemont, I noticed 

 good examples of delta terraces on at least three small streams, that come in from 

 the mountains of Coleraine, Heath, and Rowe, on North river, Mill brook, and 

 Pelham brook, as is shown on Plate IV. 



The Moraine Terrace is certainly one of the most remarkable of all the forms 

 of surface geology, as it is one of the most difficult to explain. It is now more 

 than twenty years since I first attempted to describe this phenomenon, and though 

 I have called in the aid of drawings, I feel that I have yet given but an imperfect 

 idea of it to those who have not seen it in nature. Wherever I have travelled, 

 however, these singular elevations and depressions of sand and gravel have awak- 

 ened my attention, and the localities have multiplied beyond the power of memory 

 to recall. I do not, however, recollect to have met with them anywhere, save in 

 such circumstances that in the drainage of a country the spot must have formed 

 a shore sufficiently steep to have arrested and stranded floating icebergs. I will 

 refer to a few localities. 



To begin with the eastern part of Massachusetts, we find these terraces near the 

 extremity of Cape Cod, in Truro, of sand, very strikingly piled up and gouged out. 

 At Plymouth they are more gravelly. In passing west from the coast, we meet 

 with the first general rise of the country. In about twenty miles, and all along 

 this ancient coast line in Connecticut, Massachusetts, and New Hampshire, we find 

 these terraces, not quite so high, however, as in more mountainous regions. In the 

 valley of Connecticut river, all along its eastern side, where the alluvial plain 

 abuts against the bounding hills, they are very common. Still more striking are 

 they along the western foot of Hoosac and Green Mountains, in Massachusetts and 

 Vermont. Let any one pass from Dalton, in Berkshire county, to Cheshire, along 

 the Gulf Eoad, and he will be a witness of this phenomenon in its grandest form. 

 It is very striking, also, in the east part of Granville, in Hampden county, at the 

 west foot of Sodom Mountain, in a region scarcely penetrated by roads. 



These singular forms of the surface do not occur in the lowest and most perfect 



terraces, but generally as a part of the highest in a district. The materials are 



always rounded and sorted, and water has most unquestionably played an important 



part in their production. But I am sure that no logical mind, accustomed to geo- 



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