MKMoinAi, OF c. n. [ht(H('0(;k 



69 



coiuliR-ted I'lirtlu'r ru'ld-work. In which the survcviMl geologic .sections 

 crossing New Hainpshiiv were iiureased to eigliteeii, with collection of 

 al)out 5,000 rock specimens. Improved drawings of the profiles, colored 

 geologically, were prepared for the new Rutterfield Museum of the col- 

 lege, and another large relief map of the State was made, on the same 

 horizontal scale of a mile to an inch, but with a vertical scale of a half 

 mile to an inch, the White Mountains being tlius represented as about 

 two inches high. This map has geological coloration like tiie sectional 

 profiles. 



In development of knowledge of the Ice Age and its drift formations, 

 Professor Hitchcock made very important studies. On the Vermont 

 Survey he mapped the terraces of valley drift bordering the Connecticut 

 IJiver, which were again the chief subject of a chapter by the present 

 writer for the Survey of Xew Hampshire. In 186(S he gave a lecture 

 in Xew York and Brooklyn, in which he asserted that the hilly and 

 ridged drift deposits called the backbone of Long Island for its entire 

 lengtii are the terminal moraine of. the continental ice-sheet. Ten years 

 later I examined and described this moraine and its extension eastward 

 on Marthas Vineyard and Xantucket. Its western course has been 

 traced across Xew Jersey, Pennsylvania, Ohio, and other States, to 

 Wisconsin, Minnesota, the Dakotas, and onward to the Rocky Mountains 

 and the Pacific coast. Smootlily rounded and oval hills of the glacial 

 drift, which in 18T6 Professor Hitchcock described and named lenticular 

 liills in Xew Hampshire, are since called drumlins, from their name in 

 Ireland, where many such hills were earlier mapped. Long ridges of 

 gravel and sand, deposited in ice-walled channels of streams during the 

 final melting and departure of the ice-sheet, were described l)y G. F. 

 Wright in tlie third volume of tlie Xew Hampshire Survey, being, then 

 called kames, as in Scotland, for wliich later their Irish name, eskers, lias 

 come into general use. 



Olacially transported l)oulders were found l)y Professor Hitchcock in 

 1ST.") on the summit of Blount Washington, about 1,000 feet above the 

 former recognized upper limit of the glacial drift, proving that for some 

 relatively short time the great ice-sheet entirely enveloped this mountain. 

 The name Chamjdain was given l)y him to fossiliferous mai-ine clavs in 

 the Saint Lawrence Valley and adjoining Lake Champlain, whicli overlie 

 tlie glacial drift and show that this part of our continent was somewhat 

 depressed below its ])resent height when tlie ice-sheet was melted awav. 

 Hence the closing stage of the Ice Age is naiiie(l the niaiuphiiii stage or 

 cpocli. 



