SOME OBSERVATIONS ON THE CRUSHING EFFECTS OF 
THE GLACIAL ICE SHEET. 
W. G. Tight. 
It has been our privilege to devote considerable time of late to 
the study of the drift deposits of Licking county, including also a 
study of the effects of the continental glacier in modifying the topog- 
raphy. This region offers a very interesting field for work, as it is 
located just on the limiting line marking the probable advance of the 
ice cap. Part of the county being beyond the margin of the ice, and 
part evidently effected by it. 
While the work is intensely interesting, it is at the same time ex- 
ceedingly difficult, due to the subsequent action of the waters of the 
Champlain and Terrace epochs, thus working over and destroying 
the glacial deposits, and also on account of the character of the rocks 
acted upon, which are of a soft character and easily affected by disin- 
tegrating forces, so that the direct action of the ice, such as glaciation 
and scoring, is entirely lost. A more extended account of the results 
of the work done on this subject will appear in some subsequent vol- 
ume of the Bulletin. At the present writing we desire to call atten- 
tion to a few observations made at different points in some of the 
numerous quarries of the county on the character of the disintegra- 
tion, and we offer them at this time, with the suggestions which they 
have aroused in our mind, not as representing any finished work, but 
more to direct attention to the subject and elicit any criticisms and 
suggestions which may be offered, and to learn whether anything has 
been done in this direction, and if so, where the desired literature 
concerning it may be obtained. Any information on this subject will 
be thankfully received. Our attention was first directed in this line 
while on a little geological excursion with our class. We were struck 
with the peculiar fractured appearance of the waste or surface rock 
above the solid stone employed by the quarrymen. The first quarry 
studied is located a mile north of Newark.' Plate A is from a photo- 
graph showing about half of the quarry, which is located near the 
top of a high hill about a hundred feet above the creek bed. The 
