

24 



facility and quantity, than by the course heretofore pursued, and with a great 

 saving of expense. 



An adit is to be connected with the reduction works by a train road. The adit 

 has been driven through the trap rock for a distance exceeding one hundred and 

 forty feet, at an expense of thirty dollars per foot. 



On these large lodes, wherever they have been opened, we find the same gen 

 eral rule holding good that have been repeated previously, viz : that a very gen 

 eral increase in power is manifest the greater the depth attained. 



In this mine the increase is eighteen inches in twelve fathoms, the vein at this 

 depth being twelve feet in power. 



The Chili Mill reduces two and one-half tons per diem, the ore yielding thus 

 far an average of forty dollars per ton. 



It will be seen from the above statement that this mine, as imperfectly worked 

 as it appears to have been by the slow process of the arastra, together with the 

 absolute amount of ore reduced, which amounts to seven hundred tons only, has 

 paid the entire outlay of capital in its opening, and to the present time the yield 

 being $28,000 with the contingent and incidental expenses. 



RECAPITULATION. 



Mine opened, 1851 ; erection of new reduction works, 1855 ; expense incurred 

 for same, $18,000. 



Tuns of ore reduced per day, two and a half; average value of same, forty 

 dollars. 



Depth of main shaft, seventy feet ; length of adit, two hundred and sixty feet. 



Cost of adit, $5,320 ; cost of shaft, $1,260. 



Strike of lode, N. 30 E. ; dip 40 W. ; power, twelve feet. 



Walls of lode, talcose schist ; ores, pyriferous and gossan. 



McGHEE, Director. 



EXPERIMENTAL MINE, COLUMBIA, TUOLUMNE COUNTY. 



This mine is situated about one and a half miles north of the town of Colum 

 bia, in the County of Tuolumne. 



It was first located in 1852, and some little money and labor expended upon it 

 sufficient to fairly test the character of the vein. 



From this time until the early part of 1854, little or no labor was bestowed in 

 developing the mine. During that year a company was organized with a small 

 capital, who proceeded to erect a mill and reduction works, driven by water, and 

 continued in operation until the failure of a sufficient supply of the motive power 

 compelled them to suspend their operations for the time being. 



The capital invested in erecting their reduction works amounted to $3,602 ; and 

 at the end of a little more than four months, the mine yielded $16,150 from fif 

 teen hundred tons of ore, giving an average of a little more than ten dollars per 

 ton. 



This, however, is but a preliminary movement to a larger operation, as the 

 aggregate yield was found to pay a large interest on the capital invested. 



