390 = 7. ©. Chamberlin—Hillocks of angular Gravel. 
sively in channels cut back into the retreating edge of the ice 
by superglacial streams.* — - 
Not to enlarge upon the subject here, suffice it to say that 
there are many features of the great branching osars that 
strongly invite the belief that they are the products of the 
drainage system of practically stagnant glaciers.+ If this view 
be sustained—and that will depend, of course, not so much 
upon its aptness as an explanatory hypothesis, as upon collat- 
eral and independent evidence that the dissolving ice sheet, in 
its closing stages, became stationary in the areas involved— 
there will be room for a wide dynamic distinction between 
these by-products of ice under minimum motion, and the kames 
associated with terminal moraines, which are the offspring of 
glaciers at a stage of nearly maximum activity. 
To what an extent it may be found serviceable to use dis- 
tinctive genetic terms for these several classes, can only be ad- 
judged when their respective prevalence, and the success with 
which they can be trustworthily discriminated, shall have been 
determined. Meanwhile the general structural distinction be- 
tween elongated osars and hummocky kames is needed to avoid 
most distinctive, though perhaps not most common, types. 
* Upham, Origin of Kames or Eskers in New Hampshire. Proc. Am. Assoc., 
TRTG, X2V; S16: 
Prof. Stone, who has studied these special forms more extensively than any 
one else in this country, expresses the conviction that the flow of the ice as @ 
whole had ceased at the time of their deposition. (Kames of Maine, p- 469.) 
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