52 ICE RECESSION IN NEW ENGLAND 



4339-4400. — Continued 



horizon. The difference between the varves at the 

 two localities seems to indicate that the water 

 depth influenced the sedimentation and that the 

 horizon, at locality 15, was deposited in rather shal- 

 low water. The case is difficult to understand if the 

 water depths were so great as 150 feet at locality 15 

 and 200 at locality 16. And so it is not unlikely 

 that the lake reached its highest level after year 

 4400 by the rising of its outlet below Middletown, 

 Conn. (cf. p. 8). This is also corroborated by 

 the fact that the varve silts in the region go 

 over in co sand deep below the highest level of the 

 lake, at locality 11, for instance, about 150 feet 

 below it. 



4398 is relatively much thicker at locality 16 than at 



locality 15. 



4399 and 4400, at localities 15 and 16, are sandy and record 



a drainage. The thicknesses, at locality 15, are 3^ 

 and 5^ inches (9 and 13 cm.) and at locality 16, 

 3% and 2?$ inches (9.5 and 6.7 cm.). 

 4401-4600. — Very good. The agreement of the curves is striking 

 even between such localities as 16 and 20, which 

 are separated by the Holyoke Range and accord- 

 ingly were very differently situated in relation to 

 the ice border. 



4404, at localities 15 and 16, is sandy and measures 4 and 

 2^4 inches (10 and 6 cm.) respectively. 



4410, at locality 15, is sandy and measures 1% inches 

 (4.5 cm.) and so is abnormally thick. 



4520-4528, at locality 20, represent a weak drainage which 

 made itself felt only locally. The thickest varve, 

 4522, is 1 24 inches (4.5 cm.). 



4551 and 4552 are silty drainage layers at localities 24 and 

 25 only. They measure 3 and \yi inches (7.5 and 

 4.2 cm.) respectively. 



