THE NEW ENGLAND STATES 35 



.'111 ice channel or tunnel. As it is known that the land there at the time 

 of final recession of the ice-sheet stood about 230 feet lower than now, 

 the pothole erosion seems probably referable to some earlier part of the 

 Glacial period, before the continental subsidence restored a warm climate 

 on the boundar}'' of the ice and caused it to be melted a\va3^ 



Another pothole, measuring about two feet in both diameter and 

 depth, attributed by Professor Stone to glacial origin, is in Paris, Maine, 

 on the side of a cliff. He thinks that the cliff caused a crevasse, into 

 which a stream fell from the melting ice surf^ice.* 



Mr Charles Fry, of Boston, informs me, by letter, of a few small glacial 

 potholes, occurring near together, about a foot or slightly less in diam- 

 eter and of nearly the same depth, observed by him on the southeastern 

 ridge of Green mountain, on Mount Desert island, at a height between 

 500 and 550 feet above the sea. 



NE W HA MPSHIR E 



Professor C. H. Hitchcock notes a pothole, 4 feet deep, on the top of 

 Swetts mountain ; one of large size on the southwest slope of Carrs 

 mountain ; and another, about two feet in diameter and depth, in Dun- 

 barton, 125 feet above an adjoining valley. Another, described from my 

 observations, is near the top of Beech hill, in New Hampton, about 600 

 feet above contiguous lowlands and lakes. This, like the one in Dun- 

 barton, is called an " Indian mortar." Its diameter is 15 inches and its 

 depth about two feet, f 



Each of these potholes was quite certainly of subglacial origin ; and 

 at least the two instances on or near the tops of a mountain and a high 

 hill seem explainable only by a torrent impinging on the rock at the 

 bottom of a moulin. 



VERMONT 



Doctor Edward Hitchcock reported potholes at numerous localities in 

 Vermont, far above any present stream, and in several instances high 

 on the slopes or ridges of mountains. They are of different sizes, up to 

 a diameter of 20 feet and depth of at least 25 feet. % 



MASSA CHUSETTS 



On the seashore in Cohasset, subglacial potholes have been described 

 and figured by Mr T. T. Bouve, showing vertical water-wearing to depths 



*Ibid., pp. 327, 328. 



t Geology of New Hampshire, vol. 3, 1878, pp. 249, 250. 



X Geology of Verraoat, 18G1, pp. 21G, 217, 703, 030, 933. 



