THE MILLERS EIVEIi DELTA. 625 



sands and clays to 290 feet at its north and and "2b'0 feet at its south end, 

 a descent of 30 feet in 7 miles, and the surface of the lii<)-h terrace shows 

 about the same descent. As this slope is wholly inconsistent with the 

 accumulation of thick beds of fine laminated clays, some ])art of this differ- 

 ence may be assigned to a post-Glacial elevation increasing northwardly, of 

 which we shall find many other indications. 



The order of events in the basin seems to have been, in brief, as follows: 

 The broad shoreward gravels of highest level began to be brought into the 

 basin before the last remnants of the ice had been melted, those on the west 

 side largely by the main stream, those on the east side by the triljutaries. 

 Then far to the south the great delta of Millers River, as detailed Ijelow, 

 was thrust across the narrow outlet of the basin, ponding back the waters 

 and alloAving the deposition of the great thickness of fine sands and clays. 

 The coarser delta deposits were continued out over the finer, nuconfonii- 

 ably in a sense, and completed the filling of the valley. 



Where the highest floods failed to plane the earlier beds down fully 

 they remain as kame ridges. When the floods ceased to rise over these 

 highest flood jjlains before the ice had wholly melted beneath them the latter 

 are kettle-holed. 



THE MILLERS RIVER DELTA. THE CANTON AND OLD COURSE OF THE CON- 

 NECTICUT. 



The section of the flooded Connecticut which we have above described 

 might very properly be treated separately as the Northfield Lake. It 

 would include just that portion of the valley which is portrayed on the 

 Warwick sheet. The valley expands at the north border of this sheet, and 

 soon contracts again to the north (PI. XXXV, C). 



The high terrace which we have followed south along the east side of 

 the valley as a narrow bench of sands applied to the high, rock}?^ valley 

 side, widens suddenly south of Northfield Farms, extends entirely across 

 the valley proper, and abuts on the west against a steep ridge, called Mine 

 Hill. The river does not, as heretofore, erode its channel down the middle 

 of this plain, but escapes southwestwardly from the corner of the basin 

 tlu'ough a deep gorge of its own cutting, between the ridge of crystalline 

 rock mentioned above and the Triassic conglomerate. 



MON XXIX 40 



