142 GEOLOGY AND GOLD DEPOSITS OF THE CRIPPLE CREEK DISTRICT. 
When sufficient precipitate has collected at the bottom of the precipitation 
tanks, it is drawn into a small monte-jus, and forced through the filter presses, of 
which there are six. Finally the presses are cleaned and the precipitate is dried, 
roasted, melted with flux, and cast into bricks. On ores of average grade an 
extraction of about 95 per cent is obtained, but since the actual loss approaches a 
constant amount, the percentage of recovery is higher for rich ores. 
Chlorine for the solution of the gold is generated electrolytically at the plant. 
A hot saturated solution of salt is treated in McDonald cells, the chlorine being 
piped away and the concentrated caustic-soda solution collected as a by-product. 
Among the principal mines from which this mill treats ores are the Abe Lincoln, 
American Eagle, Elkton, El Paso, Findley, Golden Cycle, Shurtloff, Strong, Theresa, 
and Vindicator. In April, 1904, the plant was handling about 250 tons daily. 
At the Florence plant of the same company the practice is similar, except 
that six Pearce turret furnaces are used instead of the Holthoff type. 
In the Telluride mill of 300 tons daily capacity Holthoff furnaces are used. 
The chlorine is generated by calcium oxychloride and sulphuric acid. The liquor 
from the filter presses passes through a box of finely divided charcoal and a further 
saving of 0.005 ounce of gold per ton of solution is thus effected. The chlorinated 
pulp is not concentrated at this plant. Among the mines which ship ore to the 
Telluride mill are the Ajax, Dillon, Mary McKinney, and Old Gold. 
The Economic mill at Victor, with a capacity of 300 tons, roasts after crushing 
in seven Argali furnaces and one Pearce furnace, both burning crude Florence oil. 
The chlorination takes place in seven 20-ton lead-lined revolving barrels, 171 by 8 
feet. Chlorine is generated by sulphuric acid and calcium oxychloride. The 
agitation occupies three hours. The filtrate goes to settling tanks and thence to 
five steel precipitating tanks 8 by 16 feet. Hydrogen sulphide is the precipitant 
used. After passing through filter presses the cakes of gold sulphide are roasted in 
shallow iron pans, mixed with flux, melted in a wind furnace in large graphite 
crucibles, and the gold finally poured out in 700-ounce bricks. 
The latest mill to be built is that of the Portland mine at Colorado Springs. 
This includes a sampling department with adequate dust collectors. Ore beds are 
made up of 3,000 tons capacity, the ore being reduced to three-quarters of an inch 
in size. There are three Pearce and one Holthoff roasting furnaces, originally 
built for oil burning, but now preferably heated by producer gas. Otherwise the 
practice corresponds to that already described. 
LABOR CONDITIONS. 
The minimum wages for ordinary miners are $3 a day of eight hours, and 
machine men receive ordinarily $4 to $5 a day. The total number of men employed 
by the mines and samplers was about 5,500 in 1903, and more than this were probably 
employed in 1900 and 1901. The aggregate monthly pay roll of the camp amounts 
to $600,000. By far the greater number of men, probably about 3,000, are working 
on Battle Mountain and Bull Hill. The miners are chiefly Americans, comparatively 
few foreigners being employed. 
With fair wages, a healthful climate, and comparatively cheap living expenses 
there would seem to be no reason for such labor troubles as have twice afflicted the 
