398 E. Hitchcock on a Bowlder in Amherst, Massachusetts. 
shape, the four longest sides being nearly at right angles to eack 
other, while the ends were more irregular. Its medium length 
was 64 feet; its breadth, 54 feet; and its thickness, 2% feet. 
Consequently its weight was about eight tons. It was determined 
to raise it out ofits bed; and when this was done, I was sur- 
ginally, except that the ends are inverted. Deeply engra 
upon one end are the words,—“ The Class of 1857 ;” that bein 
" — when they graduate. 
How now shall we explain the parallel striation on four sides 
of this bowlder? Striated blocks I believe, have generally been 
regarded as having been frozen into an iceberg, or a glacier, 
which grated along the surface. But this explains the stri only 
on one side. For if the bowlder should happen to have been 
frozen into. a second iceberg, or glacier, how small a chance 
would there be, that it would be scratched in a parallel direction 
southern journey, it were frozen into the bottom of an iceberg. 
As this grated over the rocky surface, it would soon be smoothed 
and : Nor is it strange that in such a manner the erosioD 
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