II 
Pre-Wisconsin Drift in Finger Lake Region 
But the old drift in the minor valleys of condition (3) has suf- 
fered less from ice-erosion. The stage of development of these 
minor valleys, and their degree of transverseness to the moving 
ice are important factors in controlling the extent of ice-erosion 
in them. 
Furthermore, under all these conditions we should find more old 
drift preserved in areas where during either pre- or interglacial 
time the drainage has suffered rejuvenation. The chances of 
such old drift being later revealed is greater in the transverse drain- 
age lines of condition (3). 
INHERENT CHARACTERISTICS OF OLD DRIFT THUS PRESERVED. 
Compactness. The obvious resistance which this old drift 
offers to stream- or wave-cutting is its most characteristic feature. 
The pressure of the overriding ice-sheet has not only rendered 
such drift very compact, but there should be seen, particularly 
where the original deposits were fine in texture, a foliation due to 
the pressure. Lamination also might be contemporaneous with 
the formation of the deposits, but in any event it would be induced 
by great pressure. The effect of the superincumbent weight of 
a second ice-sheet should be noted, where the drift has been dis- 
sected into rather vertical cliffs, in the tendency of the pebbles 
and bowlders to overhang. 
Color. In the region under discussion ice-erosion has had, in 
general, favorable conditions for effectiveness. The highly weath- 
ered zone of an earlier drift-sheet would be most disturbed or 
eroded by another invasion of ice, except in the case where ice-ero- 
sion had fallen short of the unweathered zone. The part of this 
earlier sheet remaining should have its original color, or at least 
the color which it had just previous to being overridden. Its 
present color need not necessarily be fresh or untarnished, but there 
is strong presumptive evidence that no color alteration has occurred 
since the retreat of the Wisconsin ice which furnished the debris 
for a protective burial of this older drift. 
