Editorial Conniiott. 43 
EDITORIAL COMMENT. 
UIUrXTlOX OF I'REGLACIAL STREAM-FLOW IN CENTRAL 
NFW YORK. 
In the March iiunihcr of the Journal of Geography is an 
article by Mr. l-'rank Carney entitled, "A Type Case in Diver- 
sion of Drainage." which contains an error that should not be 
allowed to pass uncorrected. 
The author makes the valley of Fall creek at Ithaca the 
lower course of a preglacia! river, a trunk stream, draining a 
large territory on the east and northeast, and debouching into 
the Cayuga valley by the present Fall creek channel. One prin- 
ciple and one fact will together be sufficient to show the im- 
possibdity of the postulate, and that no considerable preglacial 
stream could possibly have followed the course given in his 
map. 
On.e of the elementary principles of the modern science of 
f^uviology is that a vigorous stream will in time grade its chan- 
nel consonant to its baselevel, whether that baselevel be another 
stream or static water. Certainly the millions of preglacial 
years gave the suppositious Fall creek river all the time it need- 
ed to produce full gradation. It could not possibly have re- 
tained in its path any cataract or cascade or even rapids, and it 
would have opened a broad valley, graded of necessity to the 
Cayuga valley. This would be equally true whether it was 
tributary to another stream in the Cayuga valley or was itself 
the main stream. But now as a matter of simple fact there is 
no such tributary valley joining the Cayuga valley at Ithaca. 
Fall creek today plunges down a rock slope several hundred 
feet to reach the Cayuga level, and is evidently in a postglacial 
gorge. Xor is there any buried nor any deserted valley which 
could have been the product of the hypothetical stream. 
It might be claimed that the gradation plane of the hypo- 
thetical river is above the Cornell University level, in the open 
section of the Fall creek valley, at about the i lOO foot contour. 
But this would require a glacial or postglacial excavation of 
CavUga valley of a thousand feet. Even the most extreme ad- 
vocates of great glacial erosi(^n will hardly venture to make that 
claim. 
