EASTERN SLOPE OF THE BLACK HILLS. 259 



observation of Altair gave for the latitude of the camp, 41° 8' 2''; 

 long. 105° 24' 11.'' 



Sunday^ September 29. — Ther. at sunrise, 28°. After passing 

 through about two miles of pine and aspen woods, the country be- 

 came a rolling prairie, which obliged us to wind about considerably 

 among the hills to avoid the undulations of the ground. Our gene- 

 ral course was east for eleven miles, when, descending the eastern 

 slope of the ridge, wCf struck upon the heads of a little stream 

 issuing from a rugged canon of red feldspathic granite, at the base 

 of the hills, and flowing into the plain below. We learned from a 

 band of Cheyennes, who paid us a visit about sundown, that this 

 was another branch of Crow Creek. Here the main ridge of the 

 Black Hills suddenly falls off into a range of lower elevation, 

 which again slopes to a plateau of clayey and earthy marl. The 

 timber which had clothed the ridge ceases upon reaching the plain, 

 but the stream is fringed with willows. Where the creek issued 

 from the canon, wild cherries, and yellow, red, and black currants 

 occurred in great profusion and fully ripe. The yellow variety 

 was particularly good, resembling in flavour a mellow sour apple. 



From our noon halt of yesterday, the formation has consisted 

 chiefly of massive red feldspathic granite, with an occasional heavy 

 out-crop of ferruginous quartz. Following down this branch for 

 four miles, we encamped on its left bank, with good grass and water. 

 A village of Cheyennes was encamped a short distance to the north 

 of us, who, as soon as they descried our party, immediately paid 

 us a visit. They hung around the cook-fires till the guard was set 

 for the night, when I notified the chief of the fact, and desired 

 him to send his people away, at the same time informing him that 

 should any attempt be made during the night to disturb our ani- 

 mals, the guard had positive directions to fire upon the marauders. 

 He made them an harangue to this effect, and they immediately 

 left us, some for a ride of ten miles back to the vicinity of our 

 morning encampment, whence they had followed and accompanied 

 us during the day, partly from curiosity, and partly from the hopes 

 of a plentiful meal. Day's march fourteen and a-half miles. Lati- 

 tude by observation 41° 9' 3".5; longitude 105° 8' 24". 



Monday^ September 30. — The camp was up long before daylight, 

 and we were on the road by sunrise. Finding that the branch of 

 Crow Creek, upon which we had encamped, passed too much to the 

 southward for our purposes, we turned our faces to the north, and 

 followed along the base of the Black Hills, about four miles distant. 



