74 Proceedings of Indiana Academy of Science 



that he who is geologically trained may read with ease. The reason for 

 the superiority of the one stream over the other is not so indubitable. 



In the NW. i^, SW. V^, Sec. 15, Tp. 14 N., R 4 W., on the Arnold 

 farm, there is a stream flowing in a general northerly direction, divid- 

 ing into an east and west fork at the north fence of the Arnold farm. 

 The east fork is an intermittent stream; the west fork is fed, in its 

 main branch, by a limestone spring which flows throughout the year. 

 In figure 3, this branch is shown as a permanent stream and so it would 

 be, but for the swallowing of the water in its lower course by the numer- 

 ous limestone joints. At the spring, the limestone is not covered by as 

 great a thickness of glacial till as farther down stream. It is therefore 



Fig. 2. An intcnnrdiate stage between that shown in figures 1 and .T in the 

 drainage relations. 



believed that in the earlier history of the west fork it was a true 

 permanent stream due to the spring and that the water did not then 

 lose itself in the joints, where its flow would give the west fork the 

 advantage over the east fork. Therefore a branch of the west fork 

 would have an advantage over a branch of the east fork. 



Shortly above the junction of east and west forks, between the 

 forks, rises an elongate oval hill about 20 feet above the level of the 

 west branch. This hill is entirely surrounded by valleys. It is com- 

 posed of boulder clay and, except for its marked oval form, is of the 

 Indian-mound type. Immediately to the south of the hill, an inter- 

 mittent branch joins the main west fork on the east. Up stream, this 

 branch runs first in a general east-west direction, then when well beyond 



