GLACIAL DRIFT. 2$/ 



and nearly all the boulders seem to have come from that direction. The 

 schists like those at Portland, Me., cannot be indisputably proved to have 

 come from that quarter ; but if there were evidence' of a south-west cur- 

 rent, I should refer to that locality for their origin. The most difficult 

 fragment to explain is the piece of limestone about a foot through, found 

 at the eastern edge of the cliff. It is drab colored, weathering reddish, 

 and tarnishes quickly after exposure. There is nothing like it in New 

 Hampshire, nor in western Maine. It is like some limestones from the 

 vicinity of Machias, 190 miles distant north-east in an air line, or New 

 Brunswick, much farther. I inquired whether ballast from schooners 

 might not have been thrown out upon the beach ; but those who have 

 lived here for many years thought the stone could not have been brought 

 in that way. Our conclusion is, that the stone came from the bank, more 

 likely the upper than the lower division, and that its original source was 

 towards the north-east. We need, however, confirmatory observations 

 before throwing down the gauntlet in favor of this proposition. 



Dover. 



The locality examined is the excavation in the kame half a mile north- 

 west from the post-office, made by the Dover & Winnipiseogee Railroad, 

 figured and described upon page 158. The previous example was in till; 

 this is in material derived from the modification of the upper till, and the 

 stones have travelled somewhat further than to their place of deposit 

 from the glacier. The largest stone I have seen in any gravel deposit 

 in the state occurs here, weighing sixteen tons. There are others two 

 thirds the size of this, all of mica schist, with rough edges, showing only 

 a short carriage. It is the rock of the neighborhood, and consequently 

 the most abundantly represented among the pebbles. Others are fine- 

 grained granites, Montalban schists. Concord granite, trap rocks, White 

 Mountain porphyry, red porphyry (like that occurring upon Mt. Lowell), 

 Albany granite, Tripyramid diorite, sienite (like that on Red hill), sienite 

 with two kinds of feldspar, and the granite of Hart's Location, such as 

 has been quarried on Sawyer's river. Probably ten per cent, of these 

 stones came from the White Mountains, some of which can be shown to 

 have been carried more than sixty-five miles. Perhaps most of them 

 might have been derived from the Ossipee group, within forty miles. 



