602 GEOLOGY OF OLD HAMPSHIRE COQXTY, MASS. 



It is also quite jjossible that the Ashfield Lake did di-aiii into the Con- 

 wav Lake, flowing- back south to fill the cul-de-sac described above with- 

 out ovei-flowing to the south, and that for a mile east along the South 

 River Valley it left no deposits. My atteu,tiou w^as not closely dii-ected to 

 the point when on the ground, and my opinion was formed from a xiew of 

 the entire area from the top of the highest hill after I had gone carefully 

 over the whole region. 



THE BUCKLAND LAKE. 



If we follow the outer contom-s of the Ashfield Lake where the sands 

 border on the rocks, we shall find them converging just north of Great 

 Pond upon a naiTOW, rocky canyon, and it is plain that the waters came 

 through this passage for a long time and Avith gi-eat force, bringing tlie 

 sands winch extend south fi-om its moutli. The di-ainage of Great Pond 

 is southward, but a small rise of its waters would send it north through 

 this gorge. On entering- this gorge one expects it to. rise among the hills 

 and terminate as a mountain glen, and expects to find the brook which has 

 brought down the great volume of sand, but a short distance north the 

 valley widens somewhat and sinks 300 feet with great suddenness, so that 

 it has been very difficult to carrv the road down to its bottom. One sees 

 immediatelv that the ice must have filled this deep valley (b^^, PI. XXXV, 

 A) when the waters swept across its back and tlirough the naiTOw gorge 

 bearing the gi-eat volume of sands which now form the Ashfield Plains, for 

 otherwise the deep valley to the north must have been filled first. That it 

 was not filled and then reeroded is certain from its bare, rocky, and bowlder- 

 covered side.s and from the abundant openings made by the new road car- 

 ried down to the vallev bottom. Taking- this road, we go down sharply to 

 the valley bottom over till, and along the bottom for a short way also over 

 till, when we come suddenlv iipon a gi-eat bank of fine, well-bedded sands, 

 about 33 feet high, with a slope as regular as an earthwork, facing us (i. e., 

 facing south), and extending right across the valley and resting against its 

 ■n^alls. It is like a dam, only breached at the center by a brook which i-xms 

 north, and we seem to be in the bottom of an abandoned mill pond. Climb- 

 ing to the toji of the slope, we find it is the southei-n tennination of a great 

 body of sand Avliich once filled the valley from this point north across Buck- 

 land to Buckland Center, and which, though now largely eroded, can be 



