276 GEOLOGY OF THE BLACK HILLS. 



pebbles and bowlders from the disintegration of the Potsdam conglomerate, 

 and only a small portion is derived from the more recent erosion of the 

 slates. Partly from this cause and the flat character of the region, there 

 are few elevated gravel bars on this stream of any practical value. The 

 slate benches and low hills at the bends and forks of the creek are covered 

 in places with a thin layer of gravel, which, wherever tested, gave never 

 more than a color of gold. 



There are a few low bars on the larger branches of Box Elder which 

 may be found to contain gold in workable quantities, but the only gravel 

 deposits of any size are in the. flats along the stream and its numerous 

 branches. Several days were spent in prospecting on this stream b} 7 a 

 party of twelve miners who were assisting me at the time, but we failed to 

 find gold in paying quantities in any of the flats or bars which were tested. 

 Prospecting in the caflon in the limestone, the bed-rock was found bare in 

 many places, but not a color ol gold was obtained either from the small 

 gravel deposits or by "crevicing" in the bed-rock, though tests were made 

 in every favorable-looking place for several miles down the canon. 

 Below where the water sinks a high bar was found at the forks of two 

 canons, nearly 100 feet above the present channel, but no gold could be 

 found in it on panning. 



The miners who prospected on Box Elder the past summer before they 

 were removed from the Hills did not find gold in quantities enough to 

 encourage them to stake out claims or form a district. 



Elk Creek was explored by the topographical party, but was left un- 

 touched by the miners, very few being aware that such a stream existed. 

 Gravel flats and low bars are reported on this creek between the canon in 

 the slates and the canon in the limestone, which promised well as far as 

 could be judged from external appearances. In reviewing this district, 

 which it is but justice to state has been only very little prospected, I may 

 record a small water supply which fails in many places in the smaller 

 branches after August, a grade hardly greater than that on French Creek, 

 and gravel deposits which are comparatively of moderate extent and not 

 found to be rich in gold as far as they have been tested. 



