DRUMLINS OF CENTRAL WESTERN NEW YORK 4I9 



two cliffs midway between Eighteenmile and Rice creeks, southwest 

 of Oswego. 



The best longitudinal sections are the one east of Juniper pond and 

 the one halfway between Eighteenmile and Rice creeks. The lighter 

 colored top layer is well shown in the three cliffs east of Port bay„ 



It should be understood that the distinctness of the bedding 

 varies with the degree of moisture and the lighting ; and that it may 

 be subject to change with depth of cutting and so vary with time. 



Formation : theoretical mechanics 



Thus far this writing has been of a descriptive character with 

 only a modicum of reasonable inference. It is now time to take up 

 the philosophical side of the study and if possible explain the 

 origin and manner of making of the drumlins. In the earlier writings 

 on these structures the question of their genesis naturally received 

 much attention, but without confident conclusions. Probably no 

 geologist doubts their glacial genesis but the precise manner of their 

 formation has been in question. Two general views have been held, 

 one that they are overridden and reshaped moraine drift, the 

 other that they are constructional forms, built up ab initio by the 

 moving ice out of its ground moraine or interglacial drift. That they 

 received their form by the molding effect of the overriding ice sheet 

 seems too evident to be questioned. 



The idea that drumlins were primarily moraine masses may be 

 true of some drumlins, and possibly of some forms in New York ; 

 but it certainly does not apply to them in general. The distribution 

 of the drumlins is not in accord with the theoretical location of any 

 former morainal belts ; and this conception takes no account of 

 isolated drumlins in some regions, or groups of drumlins far removed 

 from suggestions of other drift masses. Moraine deposits are 

 expected to lie in continuous belts. Furthermore, no moraines of 

 such breadth and quantity of drift as are held in the Rochester- 

 Syracuse drumlin area are found in New York, probably not in the 

 Eastern States. ^ 



I It should be admitted that the full history of the ice work in New York and New England 

 is doubtless more complex than we now realize, and that probably there was ice invasion with 

 its attendant frontal waters previous to the Wisconsin epoch. We now see the deposits as the 

 last ice sheet left them, and while we must take the phenomena as we find them and study 

 them as they lie we must not ignore the probability of an antecedent and different condition. 

 However, it would be unscientific to minimize the facts before us and magnify the unknown or 

 theoretical features. 



