101 



rtnd sandKfroTios of the Uppei" Mississip[)ian. The i'csiilt of this condition 

 was that the water in the Avestern branch of Indian creels, a mile of more 

 south of Blanche, sank and reappeared in a great spring in the head of 

 Blair Hollow a half-mile farther west. A similar thing occurred less than 

 a mile northeast of Blanche and again about a mile and a half farther 

 northeast. These sinks are the largest, or most extensive, on the quad- 

 rangle. As we approach the heart of the plain farther east the sinks be- 

 come smaller and less conspicuous, the smaller ones not being shown upon 

 the map. 



On the eastern side of Indian creek valley we have large sinks. One 

 of these is just north of the Water Works pond. Here the drainage enter- 

 ing the sink flows into the pond through Stone spring a few hundred j'ards 

 farther south, entering tlie Clear creek valley, being diverted from Indian 

 creek into which tlie surface drainage once flowed. Southeast of this there 

 is a large sink east of the County Farm which receives the drainage of a 

 large region to the north which normally belongs to Indian creek drain- 

 age but appears at the surface as a large spring in the north side of the 

 branch of Clear creek valley in the N. W. :1 of Sec. 24, nearly two miles 

 south of the sink. The large sinks south and northwest of Leonards 

 Sclioolhouse have their outlet at Leonards ;\Iill by the house in the head 

 of the deep valley a half-mile south of the sclioolhouse. Rags put in the 

 upper sink are said to reappear at Leonards Mill. 



From the foregoing it will be seen that the headwaters of Indian creek 

 have been diverted into Richland creek and Clear creek by subterranean 



Fig. 20. A somewliat diagrammatic profile of a section across tlio valley of 

 Indian creek into a tributary of Clear creek on the right and tributary of Richland 

 creek on the left. The liigli points on either side of tlie figure are the old divides 

 between the three drainage basins. It illustrales the manner in which Indian creek 

 has been robbed of its waters soutliwest of Bloomiugton. The dip of the strata has 

 favored Richland creek. 



piracy. On the wrst this piracy is fa^'ored liy the dip of the limestone and 

 on the east it has taken place against the dip, which is very gentle. The 

 sinks near the outk>ts of the underground streams are large, while those 

 more remote and younger are smaller. The smallest are not represented 



