216 Association of Geologists and JVaturalists. [Oct., 



been forced over it, polishing and striteting its surface. If water 

 was the agent, it would appear as if it should have acted equally 

 on the depressed or hollow surface. 



Professor Hitchcock said that the rock referred to by Professor 

 Adams, a representation of w^hich was drawn on the black-board, 

 was a miniature representation of the mountains of New England. 

 Mountains Monadnock and Holyoke, w^ere prominent examples. 

 They are all rounded and polished with striae running in one 

 general direction over their surfaces. It was evident to his mind 

 that whatever body produced these effects, was held in its place 

 by a mighty agency, and that it would have turned to the right 

 or left when it encountered the resistance of the mountains, if it 

 had been possible for it to have done so. Striae are not only 

 worked upon the rocks, in situ, but deep valleys are cut in their 

 surfaces. And it is only on the struck side that these marks are 

 to be observed. He had arrived to the conclusion that whether in 

 the form of an iceberg or a glacier, it was ice in mass which had 

 produced the effects above referred to. He could not believe that 

 waves of translation were of themselves sufficient to accomplish 

 these results. 



Professor Silliman asked Captain Wilkes if it was within his 

 own knowledge whether the iceberg in the Southern Ocean, along 

 which the vessels of the Exploring Expedition coasted for some 

 60 or 70 miles, was attached to the coast or was afloat. He re- 

 plied that it was not afloat. Mr. Redfield could generally coin- 

 cide in the views expressed by Professor Hitchcock. He felt in- 

 clined to admit that icebergs were the principal agency in caus- 

 ing the striae, rounded and polished surfaces of the rocks of this 

 country and Europe. He did not believe that there w^as any such 

 antagonism in the glacier and iceberg theories. It was difficult 

 to explain on the iceberg theory how the different stiiffi had been 

 produced, but he believed it more difficult to explain the same 

 phenomenon on the theory of the glaciers. Waves of translation 

 have been unfrequent. 



M. Desor remarked that scratches w^ere observed on the moun- 

 tains of Scandinavia at a height of 6000 feet, on the W'hite 

 Mountains, N. H., at a height of 5000 feet. Mount Washington 

 w^hich is some 5300 feet high, is not scratched — its top is cover- 

 ed with loose boulders, presenting a fine specimen of what has 

 been denominated a lake of stones. Just beneath the summit of 

 this mountain the scratches take the general direction of the 

 scratches in the harbor of Boston. The scratches are observed at 

 a height of 5000 feet, 10 feet, and below the surface of the water, 

 but to what depth is not at the present time known. The same 

 is true of the mountains of Scandinavia. The glaciers of Green- 

 land do not run beneath the sea, but form a vertical wall at its 



