THE COMSTOCK MINES. 



109 



Cost of Tunneling in the Gould and Curry Mine, including Labor and Materials . 

 (Length of tunnel, 1,465 feet, at a depth of 200 to 400 feet below the surface.) 



Excavation 



Timber 



Lumber 



Spiling 



Framing and placing timber 

 Track iron and screws . 

 Picks and drills .... 

 Powder and fuse .... 



Candles 



Air boxes 



Total 



23. 559 64 



Total cost. 



Per foot. 



$15,932 50 



$10 87 



3, 120 60 



2 13 



549 49 



37 



807 26 



55 



967 15 



66 



322 93 



22 



562 75 



39 



305 12 



21 



654 80 



45 



337 04 



23 



16 08 



For 938 feet on the second station, at a depth of 625 feet, the cost per 

 foot for same details as furnished in foregoing table was $16 84, the costs 

 of excavation alone being $11 45. 



The above statements include nothing for costs of pumping or hoisting. 

 These w^ould of course vary considerably, according to the amount of other 

 works in progress in the mine, among which the total costs of pumping and 

 hoisting might be divided. 



On the fifth station, where the rock was much harder, the cost of excava- 

 tion for 406 feet was $16 92 per foot. For details as given in foregoing, 

 including excavation, $20 93 per foot ; and adding the proportionate costs of 

 pumping and hoisting, an aggregate per foot of $36. 



On the sixth station, for 297 feet, the cost per foot for excavation alone 

 was $18 30, and for details, as stated in table, $22 94 ; and adding proportion- 

 ate costs of pumping and hoisting we have an aggregate of $40 97. 



It should be observed that the pumping and hoisting costs are large 

 because at that time but little other work was in progress in the mine. 



Stoping or Beeasting. — The vein, or its ore- bearing portion, being 

 reached by a drift or tunnel proceeding from the shaft, the work of extrac- 

 tion begins and is almost invariably conducted by overhand stoping. The 



