tNDlAX REMAINS OX Tlt?^ TJPPEl? YliLLOWStONK. 581 



A heard of burt'alos or deer was carefully siuroimdcd by the Indian 

 linnters, and then gradually driven toward the opening' of the drive, 

 which was over half a mile wide. Once within these lines, the hunt- 

 ers drove the herd toward the blull". waving their blankets a^i they rode 

 forward. The terior-strickeu animals rushed toward the ])recii)ice, 

 keeping away and turning' back in fright from tlie lines of ''fence," 

 which gradually conviu'ged toward the cliff. At last, in a wild staiu- 

 pede, the frantic animals were driven over tlu^ edge of tlie ])re(*ipicc, 

 where those who wei'c not killed outright wei'e dis)»atched by another 

 party of hunters below. Only spears and arrows were used below the 

 cliff, because the lunse of lirearms would frighten back the animals 

 approaching the edge of the bluff. Among the mass of crunilding 

 white bones beneath this Buffalo Bluff' (as it is called here), where so 

 many wild animals have been slaughtered, you can to-(hiy occasion- 

 ally find spear and arrow heads, beautifully formed of shining black 

 obsidian, or \'olcanic glass, the material being found in large (pianti- 

 ties OM the great i>lateau of the Yellowstone National Park. 



