486 F. O. JONES 
in place on it, which would make 8 feet the minimum thickness. 
The width and length could hardly have been less than 100 feet each, 
or a total of 80,000 cubic feet. It is probable, however, that the 
original dimensions considerably exceeded the figures given. 
A further evidence of the pressure exerted by the ice is a V-shaped 
fault in the face of the quarry 90 feet north of the slide. The first 
noticeable disturbance of the strata is just above a 6-inch sandstone. 
From that point the width of the fault regularly increases until the 
top of the exposure is reached (11 feet), where the width is 7 feet 
and the vertical throw about 20 inches. The 6-inch sandstone can 
be traced northward from the fault for more than 200 feet, and the 
ae 
eS ee ee ee ee 
Voigkts quarry, Elmira, N.Y., showing rock displaced by glacial ice (Not drawn to scale). 
whole amount of rock moved may have approximated half a million 
cubic feet. 
Although rare, Voight’s quarry does not contain the only preserved 
example of glacial rock-shding. Another instance occurs in an old 
quarry at Pine Valley, some six miles farther north and on the western 
side of the valley. It was first noticed by Professor James Hall, 
and by him described as follows in the Third Annual Report oj the 
Fourth Geological District:* 
At the last-named quarry I observed the singular fact of non-conformable 
strata, as yet the only instance noticed, and which various circumstances seem to 
render incredible. The strata are parts of the same mass, once continuous, 
the lower dipping south at an angle of four or five degrees, and the upper dipping 
north at about the same angle; anda short distance farther south the whole mass 
t Albany, N. Y., 1830. 
