REPORT OF THE DIRECTOR I919 49 



The drumlins are the first item in the glacial series under discus- 

 sion and may be seen in typical development about the southwest 

 corner of Onondaga lake or in the area that comprises the southeast 

 suburbs of Syracuse. Their nature and probable origin have been 

 described at length in New York State Museum Bulletin iii by 

 Fairchild, hence will not be considered further here. 



Troughs of glacial erosion. Turning again to the photograph 

 of the relief map of the region it will be noted that four major 

 valleys, from east to west, those of Butternut creek, Onondaga creek, 

 Otisco lake and Skaneateles lake, and part of a fifth, Owasco lake, 

 are shown, all of which have a general northwest-southeast trend 

 and represent both the main channels of the ice movement and the 

 work of erosional excavation Wrought by the ice itself. On further 

 inspection it will also be evident that the Skaneateles and Otisco 

 valleys, which lie most directly in line with the ice motion, as indi- 

 cated by the alignment of the drumlins, have been gouged out most 

 deeply and uninterruptedly. In the area to the east, including what 

 are now. the Onondaga and Butternut Creek valleys, the drainage 

 from the north face of the escarpment seems to have been only 

 through valleys trending almost directly northward and, hence, at a 

 distinct angle with the ice advance deploying southeastward. As 

 indicated by the orientation of tributary valleys on the uplands, a 

 major part of the drainage of this section was to the south, though, 

 because of possible glacial and interglacial modification of their 

 courses, only inferential reliance may be placed on this evidence. In 

 any event, either because of the adverse trend of the preglacial north- 

 sloping valley gaps with respect to the ice advance, or because these 

 were smaller, there does not seem to have been in this section so 

 effective and deep scouring action as in the valleys to the west. 

 Hence, although the rock floor of the Onondaga valley is deeply 

 buried under accumulations of glacial and stream transported debris, 

 and ice erosion, accordingly must have cut down to considerable 

 depths below the present surface level, ice erosion did not carve out 

 a basin sufficiently deep to survive as a lake, as was the case 

 with the two valleys to the west. Evidence that the ice flowed more 

 freely and persisted longer in the lake valleys than in the Onondaga 

 valley is afforded by conditions at the south ends of the lake valleys 

 and is set forth below. 



The Onondaga valley, though not so deeply cut as the lake valleys 

 is, nevertheless, a typical example of a glacially eroded trough and, 

 as such, is comparable to the valleys similarly carved in which exist- 

 ing valley glaciers of the Alaskan mountains, of the Alps, of the 



