44 G. F. Wright—Glaciated Area of Ohio. 
Art. Vil.—Recent Investigations concerning the Southern bound- 
ary of the Glaciated Area of Ohio; by G. F. 
A Paper read before the Boston Society of Natural History, March 7, 1883, by 
Professor G. Frederick Wright, of Oberlin, O. 
PRELIMINARY WORK. 
In the autumn of 1880, and the summer of 1881, eg 
Jersey. I had also, fron the first, been familiar with the gla- 
cial accumulations along the southern shore of New England, 
especially those near Wood’s Holl, which Mr. Clarence King 
GENERAL REMARKS. 
The accompanying map of Ohio shows the ouudary line 
explored by me during the summer of 1882. This does not, 
as some may have surmised, represent merely a line which i 
have traversed, but a line which I have zigzagged, and along 
which I have fixed with certainty the glacial boundary upon 
nearly every mile of its course. I believe that in nearly every 
township I have been far enough south of the line here marked 
to make it sure that I was “beyond the limit of glaciation. 
Down to this line the marks of glaciation are everywhere 
abundant and unmistakable; south of it the absence of glacial 
marks is equally striking. The average depth of the glacial - 
deposit over the area in Ohio north of this boundary line is 
estimated by Mr. E. W. Claypole = Proceedings of A. A, A. 
, vol. xxx, p. 151), to be fifty-six feet. No one at all familiar 
wth the region will be Fy isposed to think this estimate 
exaggerate 
The glaciated area of Obio cousists of a rolling surface essen- 
tially like the prairies farther west, except that it was original] 
covered by timber. The pre- glacial channels have nearly all 
been buried out of sight, and it is rare that the rocks anywhere 
iy 
