Recent Changes in Gold Mining 
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The ore passes over a grizzly, the oversize from which goes 
through a Blake crusher, aud, with the fines from the grizzly, 
are elevated to a trommel screen above a small storage bin. 
The oversize from this trommel passes through a pair of cor- 
rugated rolls, then back to the same trommel, and soon, until 
it is all reduced to sand. The corrugated rolls chattered 
badly on account of the coarse feed; and the soft clayey ore 
tends to stick them so it will probably be better to use instead a 
number of smooth rolls in series. 
The fine dry ore is taken by a belt conveyor to one of the 
three sheet iron leaching tanks, 6 feet deep and 30 feet in 
diameter. It was assumed that the solution would percolate 
through the S}4 feet of dry crushed ore, even though the 
slimes were not removed; but in the actual tests the tanks 
were filled only half full. Below the level of these leaching 
tanks are zinc boxes and sump tanks; the three solution tanks 
are on a trestle outside the main building, covering the leach- 
ing tanks. 
The property was purchased without adequate sampling 
and the work was abandoned after treating 150 tons and find- 
ing that the ore averaged only $2.00 a ton. No data as to 
time of treatment, strength of solution, etc., was obtained. 
The recovery on the three tanks tried was 70, 80 and 83 per 
cent respectively. The ore is decomposed rock, occurring in 
wide zones and carrying a great deal of clay. No data was 
obtained as to the capacity of the mill. 
MINING DETAILS (SELF-DUMPING SKIPS, ETC.) 
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Many of the mines in North Carolina are based upon more 
or less flat veins and since most of the ore is hoisted in 
buckets, it is customary to sink vertical shafts. When the 
mines become deep, this requires expensive cross-cuts to 
reach the vein; hence there are many vertical shafts which are 
turned upon reaching the vein and not adapted to the use 
of a cage or an ordinary style skip. Mr. Geo. E. Price has 
overcome this difficulty at the Rudisill Mine, at Charlotte, 
Mecklenburg County, by modifying the ordinary skip, and 
