20 NEW YORK STATE MUSEUM 



of this river, some scouring of the drift would thus have been 

 accomplished. 



The mere breadth of the Flat Rock area might be explained by 

 the gradual stripping of the drift along the receding ice front, 

 without making it necessary to suppose that this belt was at 

 any one time entirely covered by a torrent. The bare surface 

 of Pine ridge, north of the deep vale of Cold brook, however, 

 makes it difficult to see how a stream of small width as com- 

 pared with the breadth of the stripped belt could have followed 

 the retreating ice front to the north of this depression. A 

 broad and powerful torrent of waters comparable to that which 

 must be evoked for the work done at "the Gulf" could reason- 

 ably be supposed to have filled this depression and scoured the 

 rocks on either side. While some of the phenomena are ex- 

 plicable on the hypothesis of a continual shifting of a" small 

 stream, there are still other considerations which appear to 

 demand a broad and powerful torrent flowing over the district. 

 Thus, in the case of the Dead Sea basin, its reported depth of from 

 42 to 90 feet appears to be greater than can be expected for the 

 work of so slight a fall as the rock cliff [see pi. 8] at its head 

 would indicate if the stream were a small one; but it is quite con- 

 ceivable that a heavy torrent might have produced the results. 



The location and vertical distribution of beaches about the 

 southeastern end of the Flat Eock area and for a considerable 

 distance along its northern margin show that the torrential 

 waters which produced this field of bare ledges discharged 

 into a standing body of water along the course of the Lit- 

 tle Chazy from 3 to 4 miles west of West Ohazy at an eleva- 

 tion at least 600 feet above the present sea level. The dis- 

 position of the cobbles, gravel, sand and clay which must have 

 resulted from the stripping of such large tracts of drift is not 

 altogether satisfactorily accounted for. It will be noted on the 

 map [pi. 26] that the marine-modified drift south and west of West 

 Chazy must be relatively thicker than is this group of material 

 north of that village, for there are no outcrops of the bed rock 

 observed in this survey in this southern belt between the 300 

 foot and llio 700 foot lines. Heavy bars and ridges of waterworn 

 drift there occur, and the unusually thick deposits are probably to 

 be attributed primarily to the wash from the flat rock districts. 



