568 GEOLOGY OF OLD HAMPSHIRE COUNTY, MASS. 



before reaching Palmer ^^llage the deep, narrow Monson Valle}- opens out 

 southwardly from this Palmer Valley and runs south across the town, 

 bounded by continuous high ground. This Monson Valley becomes a 

 narrow canyon, which is at the State line a low Avatershed with a height of 

 620 feet above the sea. A brook gathei-ing here runs north into the Qua- 

 boag, and a little farther south are the sources of the Willmansett, which 

 flows south into the Sound. The Quaboag flows west past Palmer, and 

 immediately turns north. Its valley is continued, however, at a higher 

 level (380 feet) westward to the Connecticut basin, and is now occupied by 

 the Boston and Albany Railroad. This continuation I have called the Ellis 

 Mills Valley. The Quaboag turns north in a narrow gorge lietween the 

 hill south of I'hree Rivers and Mount Dumpling, and soon turns west to 

 Three Rivers. On the north of Mount Dumpling the Ware River, coming 

 down from the north, bends west also in the narrow Thorndyke gorge, and 

 joins with the Swift River and the Quaboag to form the Chicopee River at 

 Three Rivers. 



The present gorge of the Chicopee River west of Three Rivers is the 

 last and most northern outlet of the waters of the drainage areas of these 

 three streams; and it was opened only after the ice had receded from the 

 Belchei'town plateau to the north. The Ellis Mills Valley was an earlier 

 outlet at a higher level, and the Monson Valley was a still earlier outlet 

 farther southeast and at a still higher level. This latter outlet determined 

 the level of the lake here, around Palmer, whose waters rose to the height 

 of 620 feet. The ice then occupied the Belchertown plateau and the Swift 

 and Ware river valleys and approached Pattaquattic Hill on the north and 

 west, and the ice front extended south past Palmer to Chicopee Mountain 

 (b^ PI. XXXV, D). 



The best i-emnant of this lake is seen by mounting to the top of the 

 great level sand plain east of Palmer Center and following it southeast past 

 Calkins Pond for a distance of nearly 3 miles. It has well-marked shore 

 lines against the rocks on either side, is nearly a mile wide, and whei'e, 

 on the south, it overhangs the Quaboag at Blanchardsville its sands are 

 above 200 feet thick and its broad, flat surface is 610 feet above sea level. 

 A]jproaching Palmer, its sands swing round the rocky spurs which have 

 bounded it on the west, on the east extending up the Quaboag Valley, and 

 end on the south in a great lunate delta scarp, at the foot of which the 

 river runs. The Monson Valley is its almost direct continuation southward, 



