TEEATMENT OF THE OOMSTOCK ORES. 



231 



shafting is usually arranged under the row of pans, from which shaft each pan, 

 separator, agitator, or other similar machine may be driven by a separate pul- 

 ley. The power required for each stamp of ordinary or average weight, with 

 due allowance for friction, is about one and a-half horse-power per stamp. 

 The power demanded by the pans is from three to six horse-pov^er, accord- 

 ing to their size and capacity. The expenditure of power per ton of ore 

 crushed, ground, and amalgamated, judging by the relation existing between 

 the power of the engines provided and the work performed by the mills, is 

 between one and a-half and three-horse j)ower, averaging probably about two, 

 but varying according to the capacity of the mill and the economy with which 

 the power is applied. 



