CONCLUSIONS AS TO WHITE MOUNTAIN GLACIATION. 37 



40 by 200 feet S. 30° E, The bowlders seen southwest from the lakes are too nu- 

 merous to mention. 

 Concerning the phenomena it may be remarked in general that — 



1. The direction of movement, like that common in the vicinity, is southeast- 

 erly, and the materials have been transported uphill. 



2. The bowlders have come from positions corresponding to the places of their 

 dispersal. The protogene on ]Mount Washington and Mount Jefferson is thought 

 to have been derived from Israel river valley, while the Huronian schists and 

 granites on Mount Adams have come from Groveton and Stark, a region farther 

 north. The protogenes have been transported more than 10 miles and elevated 

 4,000 feet ; the Huronian schists 12 to 18 miles or more, and the slates probably 

 30 miles. No account is taken of the transportation of the bowlders of mica-schist, 

 which may have been several miles. 



3. The location of two or three lines of terminal moraines in northern New Eng- 

 land is such as lead us to believe that their positions are not greatly changed by 

 the presence of the higher peaks. 



4. These remarks do not apply to the moraines of certain later local glaciers. 



5. The arrangement of the recently discovered fragments is worthy of notice. 

 In the first place, there are conical hills upon Mount Adams, say 50 feet high and 

 75 feet broad, consisting of the debris which has naturally fallen from a ledge. 

 These correspond with the eminences in non-glaciated regions where the rocks 

 have decayed and have been buried in their own ruins. From one point of view 

 all the Presidential mountains are reverting to this condition. Secondly, I pointed 

 out * in 1880 the fact that the angular stones are sliding down the mountain sides so 

 as to resemble local moraines. They form sloping terraces, whose tops are grassed 

 over and the escarpments consist of loose blocks which have not all reached their 

 final state of equilibrium. I fancied, also, there was a tendency in the blocks to 

 radiate from the outer edges of the terraces. They are really a species of flood- 

 plain accumulation. I observed one block of stone about 9 feet long and 3 wide, 

 which had been split from a larger piece, upon ground slightly sloping and had 

 been moved about a rod. It had crept down the slope, probably when it was icy 

 underneath. Its motion was undeniable, as its matrix was visible ; so it would 

 appear probable that all the stones in these terraces have been slowly creeping 

 downhill, but falling considerable distances when the slope was steep enough. 

 These terraces are suflficiently extensi^'e and abundant to find a place upon surface- 

 geology maps of a large scale. 



Finally, glaciation has been complete all over the White mountains. We are 

 compelled to explain why the ice has climbed from the low level of the Saint Law- 

 rence and has overridden the high INIontalban watershed. The motion of the 

 glacial ice was so irresistible that this elevated ridge has not prevented its onward 

 march. AVe can also satisfy ourselves as to the minimum thickness of the ice-sheet 

 and the slope of the surface from the point over Mount Washington to the sea- 

 level. The object of this paper, however, is not to discuss these and related ques- 

 tions, but simply to show that the evidence of glaciation over the highest of the 

 AVhite mountains has been satisfactorily substantiated. 



The scientific program was declared closed. 



■Among the Clouds, August 7, 1880. 



