Correspondence. til 
rocks, without great abrasion'.' He says: "•The north and south valley 
of lake Cayuga is several hundred feel below it [the rock bottom of Six 
Mile creek], and its depth lias without doubt been caused by glacial 
erosion."* But wlial of the evidence furnished by "the scratches on 
the polished surface of the underlying rocky table, as seen at the quarry 
[1874-7(5] in front of the buildings of Cornell University, " several hundred 
fret above the present lake surface'] 
Again, that the ice moved in a general southerly direction, up the 
Cayuga valley, into that portion of the basin which receives the modi- 
fied valleys of Cayuga Inlet and Six Mile creek, is plainly indicated by 
the presence, among the drift accumulations, "of bowlders of Oriskany 
sandstone and masses of Hamilton shale, formations which occur to the 
north." And, further, I have a distinct recollection of collecting- in 
my student days, characteristic fossils of tliese formations from fragments 
found in the valley of Six Mile creek. 
[2.] "According to this author (Simonds), the glacier divided near 
the present site of Ithaca, one lobe moving southward, the other carv- 
ing out the valley of Six Mile creek." What I did say, as shown above, 
was this: " The mass of ice which filled the Cayuga lake basin, dividing 
at its southern extremity, one part — the larger — flowed to the south, 
wearing down the Inlet valley, and the other traversed the Six Mile creek 
valley, both if which mre occupied by preglacial streams." 
By this it will be plainly seen that 1 meant that the valleys were 
moulded by ice action, not "carved" in the sense that Prof. Tarr would 
have us understand. My idea was then and is now. that these pregla- 
cial valleys served to guide the ice-sheet as it advanced toward the 
south, and that by it they were broadened and worn, giving rise to their 
present characteristic and distinctive shapes. 
[I!.] "This, which seems to be the first statement of the glacial ori- 
gin of Cayuga valley, is based upon the inability of t hi' author | Simonds] 
to conceive of the formation of a broad, deep valley by river erosion 
and transportation.' Rathe.r, my statement was based upon the pres- 
ence of stria 1 , not only in the locality mentioned, but in others: upon 
the presence of drift resting directly on a polished and worn surface; 
and upon the presence of masses of rock transported [by ice] from the 
north, i. e., brought up the valley. 
[4.]- Under " Evidence of Six Mile ci k," we find that ••these two 
valleys [Six Mile Creek and Cayuga Inlet] are the ones which Simonds 
and Foote believe to be due to ice action. They are both distinctly pre- 
glacial and are joined bj mature tributaries." Concerning t his I have 
only to say that I recognized their preglacial character and so expressed 
myself in my article by saying "both of which valleys were occupied by 
preglacial streams." In the conclusion of the original thesis occurs the 
following significant statement: "Six Mile creek we have seen to be a 
preglacial stream whose channel has not onh been traversed and worn 
out by ice. bul in main places tilled with morainic debris ■■' * *." 
bulletin, (J. 8. A., vol. v, p. 3o0. 
