121 
OOERESPO]^^DEi^^CE. 
So.MK OK Phok. 8alisi!lm:y's Okitioisms dx "]M.\n AM) Till-: Glacial. 
Tkuioo." — I am indebted to Prof. Salisbury for kindly iwinting out 
several eri-ors of more or less importance in my recent volume on 
"Man and the (glacial Period;" but so many of his criticisms are 
merely confident assertions of unproven points, that they should not 
all be allowed to pass without some notice. I will, however, limit 
myself to traversing only a few of his misplaced criticisms. 
1st. lie says (p. 14) that I should have em])hasized more than I 
did. the separation, indicated upon my map west of Pennsylvania, be- 
tween the extreme border of the glacial drift and the morainic accu- 
mulations, which he declares to be a most significant point. On the 
contrary, 1 maintain that it is becoming more and more evident that 
I'rof. Salisl)ury enormously exaggerates the importance of that dis- 
tinction. Now that ^Ir. Leverett has brought the moraines of Ohio 
close down to my border line, and that we have given closer attention 
to the so-called "'fringe" or "attenuated border," in eastern Pennsylva- 
nia and in New Jersey, it is becoming more and more evident that the 
fringe is but an appendage of the terminal moraine. The fundamental 
errors of I'rof. Salisbury's report upon " Tlie Extra-^forainic Ulacial 
Drift of New Jersey" (see An. Rep. for 1891, pp. 102, 108), were pretty 
clearly shown in the article by Prof. A. A. Wright in the Amkuicax 
Cteolooist for October, p|). 207-216. These will appear in still clearer 
ligiit upon the full publicalion of my own observations in connection 
with my associat(\ 
Prof. Salisbury, in discussing tlic exi ra-morainie drift in New Jer- 
sey, has, beyond all iiucstion, failed to distinguish lietwi-en the effects 
of the secular (lisintegration of gneissoid rocks and the post-glacial 
oxidation of morainic material, and. so far as I could lind, h(? has 
failed to make any systematic aKcinpt to determine the limits of the 
attenuated border of glacial dej)osils in the state. Following out the 
imperfectly formed |)lans of I'rof. Lewis and myself, I have already 
determined this nearly half way across the slate, and can speak with 
great positiveness astolhr fact that the prohlcm in New .lersey is 
not essentially dirt'ereiit from the problem in Ohio, and that the great 
sigiiilicance which Prof. Salisiiiiry attrihutcs to it in jiroof of jiis the- 
ory of two glacial epochs is without foundation. 
2d. Tn my paragra|)lis upon (b-umiins, alluded to by i'rof. Salisi)ury. 
I am expressly giving "'tlie plausilile explanation" of them |)resented 
l)y I'rof. Davis. Tiie view which Prof. Salishui-y combats is one to 
which Prof. Davis gives iiis posit ive assent in his concludingsentence : 
'• Under unending glacial ion. I lie whole suii'ace nuist be rubbed down 
smooth." Ft would seem scarcely necessary lo exi)lain lo >lr. Salis- 
bury that till- processes of accumulation and of degradation by both 
rivers and glaciers may be going on continuously in closely adjacent 
areas. Which shall predoinimile al any point depends largely upon 
ihe amount of material al coniniand of the mo\ ing cu n-ent . 
