81 
THe Cycle oF SUBTERRANEAN DRAINAGE As ILLUSTRATED IN 
THE BLOOMINGTON, INDIANA, QUADRANGLE!. 
By J. W. BEEDE. 
The Bloomington, Indiana, quadrangle* is the first topographic map te 
be completed in the cave region of Indiana. It is fifteen minutes square with 
contour interval of twenty feet and scale of 1/62,500, or about a mile to the 
inch. Careful inspection of the field shows it to be remarkably full and 
accurate in detail. 
While the eycle of subterranean drainage, as here presented, had not 
been discussed between us, yet all the various phases of it have been dis- 
cussed and similar conclusions independently reached by both Professor 
Cumings and the writer as the result cf tramps and class excursions over 
the cave regions of Indiana. The cycle has also been given as lectures, 
illustrated with lantern siides, in our classes. This paper has also had 
the benefit of Professor Cumings’ criticism. 
The physiographic history of the Bloomington region is such as to 
make this maj very interesting, both for the remarkable preservation of 
the older geographic features and for the recent modification of them. 
Not the least interesting, nor the least important of these, is the subter- 
‘anean Grainage. Indeed the fine preservation of the older features is 
due to the fact that the water has, figuratively speaking, soaked into the 
old peneplain much as it would into a sponge, confining its work to the 
solution and honeycombing of the rocks beneath the surface instead of 
concentrating its energies cutting it into ridges and valleys. 
The whole of the quadrangle, excenting, perhaps, the northwest corner, 
lies in the driftless area of Southern Indiana. The larger streams, except 
1The title of the paper as shown in the program was “Features of Subterranean 
Drainage in the Bloomington Quadrangle.’ After the title had been sent in it was 
realized that it would be impossible to treat the subjects in mind intelligently without 
outlining the cycle of subterranean erosion. This outline, of course, overshadows 
the minor details intended to be covered in the paper, and hence the change in the 
wording of the title. 
* Price five cents. Apply to 'The Director, U. S. Geological Survey, Washington, 
jae 
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