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Tue WEATHERING AND Erosion oF NortH AND Soutu S.Lopes. 
By GLENN CULBERTSON. 
The experience of the writer in climbing the hills of southeastern Indi- 
ana, and especially those in the vicinity of Hanover and Madison, led to 
the opinion that, in certain valleys, there was a considerable variation in 
the inclination of the slopes. 
During the last few months accurate measurements of the inclination 
of the slopes, of the depth and of the direction of trend, of four valleys 
or ravines were made with a view to ascertaining the amount of variation 
in the inclination of the slopes, and a reason for the variation where it 
was found. 
The vaileys or ravines, chosen for the measurements, are locally 
known as Butler, which is about one-half mile south of Hanover; Crowe, 
which borders the Hanover College campus on the south; Happy Valley, 
which borders the college campus on the north, and Clifty, which is lo- 
cated about two miles west of Madison. 
The hills in the region of these valleys are capped with the so-called 
bluff limestone of the Niagara formation, the Clinton, and the Madison 
beds of the Ordovician. These rocks are comparatively uniform in texture 
and hardness throughout the region concerned. Butler, Crowe and Happy 
Valley ravines are less than a mile in length, and Clifty is but little more 
than two miles in length, from the mouth to the falls, which are found in 
each valley. The depth of these valleys, however, is approximatey 260 
feet, aneroid measurement. The valleys are eroded to the level of the 
Ohio River, into which the streams occupying them empty. 
The great depth of the ravines, as compared to their length, is ac- 
counted for by the fact that the Ohio-Wabash divide in this region ap- 
proaches in places to within a mile and a half of the Ohio River. 
The streams which have formed the valleys, across the lower portions 
of which the sections were made, are all small, and, with the exception 
of Clifty, are just able to transport the materials brought into them and 
do not erode the sides to any extent. Hence, we have in these valleys 
exceptional conditions for the study of the weathering and erosion of 
slopes. 
Two sections were made across each valley with the exception of 
