50 NEW YORK STATE MUSEUM 



which in subaqueous deposits of fine material are likely to be 

 indefinite. 



OSCILLATIONS OF THE ICE FRONT: WARREN WATERS 



With the above descriptions of the stream and lake features 

 before us, it is now in order to seek the explanation which will 

 harmonize the phenomena. A brief statement of the theoretical 

 sequence of events was given in the introduction, but we can now 

 elaborate some points and give a fuller account of the principal 

 episodes in the history. 



Two main facts stand out clear: first, that all the channel series 

 from Leroy to Phelps, and all except perhaps the lowest at Syra- 

 cuse, were made along the receding ice front. Second, that the 

 Warren waters do not belong in the same episode as the channels, 

 but that they invaded central New York long afterward. The 

 distribution and vertical relation of the phenomena seem to permit 

 no other conclusion. 



The above conception implies, as a corollary, that the glacier* 

 acting as a barrier, must have been adjusted to such positions as 

 were necessary to produce the phenomena. We are required to 

 assume some advance and retreat or oscillation of the ice front, at 

 least in the Syracuse region, and a degree of seesawing of the ice 

 front as between the meridians of Bat a via and Syracuse. Cer- 

 tainly the ice barrier had to recede or back away and open low 

 passage through Syracuse and eastward in order to allow the river 

 flow which cut the channels. It is equally certain that when Lake 

 W r arren subsequently occupied central New York, at about 880 

 feet altitude, the Syracuse passes were closed [pi. 33]. But while 

 the ice front was readvanced at Syracuse, so as to hold back the 

 Warren waters, it was necessary in order that the waters could 

 enter central New York at all that the ice barrier should recede in 

 the Oakfield district. 



It is seen, therefore, that we have two critical localities; one 

 north of Batavia, near Oakfield, and the other in the Syracuse 

 district, probably the steep slope west of the city in the district 

 of Howlet Hill and Split Rock. 



On the Split Rock meridian we find all the channels or stream 

 flow features which the theory requires, the only undetermined 

 feature being the hypothetical belt of moraine which might be 

 expected to mark the limit of the ice readvance during the Warren 

 episode. This evidence has not been diligently sought, and should 



