246 MINING INDFSTEY. 



the product of tlie tailings or allowing anything for moisture. During the 

 six months to which these figures relate, the product in bullion from the tail- 

 ings was $12,730 71 ; and if this be added to the yield of the ore originally 

 obtained by the first operation, we have a total product of $233,015 88, 

 equal to 71.87 per cent, instead of 68.1 per cent, by wagon samples ; 

 or 73.12 per cent, instead of 69.2 per cent, by mill samples. If, in addi- 

 tion to this, we now allow for seven per cent, of moisture on the ore, not 

 taken into account in the assay sample to which the foregoing percentages 

 are referred, we have an actual return of 77.27 per cent, by wagon . samples, 

 and 78.62 per cent, by mill samples. 



Finally it is to be observed that the product from the tailings above given 

 is not all that is obtained from that source. The amount here stated comes 

 chiefly from the agitator. The stream of tailings passing from the settler, 

 in which the bulk of amalgam is- collected, enters the agitator, where much 

 of the amalgam and quicksilver that has escaped the settler has further op- 

 portunity to deposit itself At intervals of four or five days this vessel is 

 emptied and the accumulations are reworked in an ordinary pan, yielding 

 $18 or $20 per ton. The yield thus obtained is nearly $2,000 per month, 

 and forms nearly, if not quite, all the product represented in the foregoing 

 statement. After leaving the agitator the stream passes on, the tailings still 

 carrying enough value to make them worth further treatment; for which 

 purpose they are, in fact, sold by the mill to second parties, who do a 

 profitable business in working them again ; but this last product is not in- 

 cluded in the figures already given. The yield obtained by this final work- 

 ing of tailings is not definitely known to the writer but is generally stated at 

 about $5 50 per ton, which would add about ten per cent, more to the results 

 of the process in the mill, as already shown. 



Some mills claim to have obtained more than eighty per cent., and even 

 eighty-eight per cent., of the assay value of the ore, by the ordinary methods, 

 without including the product of the tailings or allowing anything for moist- 

 ure. This, if true, is exceptional ; but it is not impossible that a certain lot 

 of ore may have contained an unusual proportion of free gold, which, while 

 easily escaping due representation in the assay, would add greatly to the 

 value of the bulhon obtained. 



