J, DeLaski on Glacial Action about Penobscot Bay. 337 
It is quite evident that these chips, some of which must have 
n many feet in length and breadth, were not removed by a 
blow, such as an iceberg has been supposed by some writers to 
make upon the rocky sea-bottom over which it is floating. 
Again I think it evident that the blow was not given horizon- 
tally, but rather at a very considerable angle,—say from 40 to 
50°—and directed from the north; and that the breaking of the 
rocky floor.was effected by pressure. These irregular depressions 
are generally upon protuberant ledges, the “ embossed” rocks of 
such a result, if the rock which was pressing upon the 
edge, producing the furrow, had passed along beyond it toward 
sout 
horth for two miles, the land continues to rise to not less than 
AM. Jour. Sct.—Sgcoxp Sentes, Vou. XXXVII, No, 111.—May, 1864. 
44 
