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parts of the streams feeding them are still being more thoroughly taken 
under ground. A good example of this is seen in the sinks just east of the 
County Farm. The old sink is located in the angle of the road, while the 
stream now passes beneath the surface fully a quarter of a mile upstream 
to the northwest. Only the flood water now finds its way into the deeper 
siuk below. The coliapse of the mouths of caverns is excellently exhibited 
Fig. 7. Shirley Spring (East Spring), S. E. of Leonard Schoolhouse. The 
cutlet of the stream entering the sinks east of the Poor Farm and the intervening 
sinks. For abandoned, higher cave, see Fig. 30. The condition of collapse is similar 
to that shown in Fig. 6. 
in the Shawnee caves east of Mitchell, Indiana, while Lost river shows it 
still better. In both cases the roof has collapsed back for considerable 
distances and in each there are cases of collapse above the mouths of the 
caverns where either the cave or the stream is brought to light. 
When this stage of the drainage has been reached sinks have developed 
over most of the region on the interstream spaces as well as near the 
streams and most of the drainage is subterranean in the stricter sense of 
the word. ‘This stage shows the large sinks near the larger drainage lines, 
