MODIFIED DRIFT ALONG CONNECTICUT RIVER, 5 1 



An interesting dune was noted on the north-west slope of Calavant 

 hill, near the north line of Charlestown. Its height is 598 feet above the 



Fig. 13. — Section in Springfield and Charlestown near their north 

 LINES. Length, li miles. 



sea, or about 150 feet above the original plain from which it was blown 

 by the north-west winds, as indicated by the sand-drifts, now principally 

 covered by grass, that were left in its path. 



South from Little Sugar river a high terrace of till, on which the road 

 is built, extends a mile and a half to the east side of Rattlesnake hill. It 

 is nearly level-topped, and of about the same height in its whole length, 

 being 550 feet, sloping to 540 feet above the sea. This terrace is com- 

 posed of till, apparently unstratified and scarcely modified, except so far 

 as its terraced form may be due to water. This is the upper till, distin- 

 guished by its comparatively loose and sandy character. The underlying 

 member is exposed by the gully of a brook near the school-house, being 

 a blue, very compact, stony clay. 



In Springfield the whole or a part of the modified drift, lying between 

 320 and 350 feet above the sea, presents an irregularly sloping contour 

 for four miles, from the north line of the town nearly to Skitchawaug 

 mountain. 



In Rockingham, opposite the south part of Charlestown, we find two 

 considerable areas, which appear to be remnants of the river's highest 

 plain. One of these, more than a mile long by two thirds of a mile wide, 

 is in the north part of the town, bordering the river. The second is as 

 long, but only one fourth mile wide, extending to the south from near 

 the mouth of Williams river. 



Deltas. Three prominent deltas occur in these towns, the products of 

 Little Sugar, Black, and Williams rivers, with heights respectively 530, 

 520, and 500 feet above the sea. The greatest extent of these deposits 

 now remaining is in each case on the north side of the stream. Only 



