THE COMSTOCK MINES. 171 



eter by 36 inclies stroke. The other is an ordinary engine of about the same 

 power. The hoisting engines are smaller, one being 14 inches in diameter 

 of cylinder by 30 inches stroke, the other 16 inches diameter by 42 inches 

 stroke. Flat wire rope is used for hoisting. It is 3^ inches wide by 1 inch 

 thick. There are 4 boilers, each 26 feet long and 4 feet in diameter, and 

 containing two flues. They are built in two independent sets of two boilers 

 each. Only one set is in use at the same time. The consumption of wood 

 is about six cords in twenty-four hours. 



The characteristic features of the vein in this mine, and the developments 

 made by the deep shaft, have been described at such length in the foregoing 

 chapter that no further notice of these points is necessary here. It is suffi- 

 cient to say that, up to the latest dates received, the deep shaft has revealed 

 no ore-bodies of importance below a depth of 600 feet. During the past 

 three years all the ore extracted from the mine has been produced by re- 

 working the old ground, or from deposits in the upper levels that remained 

 undiscovered in earher days, but have since been brought to light. The old 

 stopes, worked years ago and long since abandoned, have been reopened and 

 worked again as virgin ground. When first mined there was a large quan- 

 tity of ore that was too poor to pay then, but rich enough to afford a profit 

 now, under reduced prices. This was then left in the mine. The ground, 

 moreover, has since caved in, and this movement has sometimes revealed new 

 sources of ore. Thus the old works have continued to afford ore in consid- 

 erable quantities. A part of this has been extracted by contractors, who paid 

 to the company a small price per ton, mining and milhng the ore on their 

 own account. More recently the company have carried on this work, and in 

 1869 did so with a very fair profit. The following tabular statement presents 

 a summary of the operations of this company, from the beginning of their 

 work. 



