GOLD AND SILVER MINING 209 



twenty years of operation was 3,300 feet. In 1886 work 

 in the lower levels had to be abandoned because of the over- 

 powering flow of \N'ater. 



Recent improvements in electrical engineering and re- 

 duction processes have led to the resumption of mining on 

 the levels which had been submerged for many years. Says 

 R. K. Colcord: 



"The ponderous and powerful hoisting and pumping 

 steam machinery' plants of the chief mining companies, 

 originally costing $500,000, $750,000, or more apiece, have 

 become dismantled, and electric, up to date machinery of 

 greater power and efficiency is being substituted and installed 

 in their place at comparatively a mere trifle of their original 

 cost. For instance, the electric hoist plant of the Union 

 Consohdated mine cost only about $10,000; Yellow Jacket 

 and Belcher, $12,000 each; and that at the C and C shaft 

 of the Consohdated California and Virginia, the most pro- 

 ductive mine of the lode, $10,000. The cost of power fur- 

 nished, as per contract with the Truckee River General Elec- 

 tric company, is $7 per horsepower, based upon a continuous 

 service and a two minute peak load. In cases of such con- 

 tinuous service this shows an actual saving of 66 per cent. 

 That is, the former rate for steam power was never less than 

 $21 per horsepower." 



Technical progress has been facilitated by modern methods 

 of business organization. The pumping association formed 

 for the purpose of pumping the water from the mines of the 

 Leadville basin may be cited by way of illustration. 



This association includes nearly all the leasing companies, 

 as well as the o\vners of territory embraced in the Leadville 

 basin. All mines operating within the association territory 

 bear the cost of pumping in proportion to their output, based 

 on net smelter returns less cost of hauling. By means of 

 counters on these pumps the amount pumped is computed 

 in gallons and charged to the association at the rate of ten 

 cents per 1,000 gallons. Those mines which pump are credited 

 with the amount of water they have raised. Taking the 

 entire district, investigation shows that the flow of water 

 which must be handled is not less than 15,000,000 gallons 



Vol. 6- -14 



