Bisbee daily review., 1914-03-01

ohutes until they intersect Then out of these raises at distance of ten or twelve feet from the chutes raises are run back SO as tc connect with each other directly over the motor drifts. After raises have been con. nected up all along the pillar they are widened out, lined with deep holes and blasted. so as to undercut the entire pillar. In this manner the whole ore block is eventually under.
 cut. permitting the entire mass to crush, which it does right effectually
 here.
 All stopes are not carried the regu- lating size. In places where the
 ground shows signs of weakness, smaller stopes are taken, and more
 is left in the pillars. Where the
 ground is very firm stopes are wider
 and the pillars thinner, this all de
 pending upon the condition met with
 in the mining There's no hard and fast rule observed in the conducting
 of this shrlnkage work.
 The Capping Comes Down In the mining the capping follows
 the crushed area with little drawing from the sides, cf the line directly
 over the ore. It Is the practice to
 take the ore rapidly from the fringe
 drift side, getting it out before the
 drifts take weight, this saving the ore
 from getting mixed with the oapping
 waste. The system operates perfect.
 ly here, and the mining cost must be low
 or a certainty there is some waste
 mixtures, but how much of the ore is vitiated we dc not know. There ntuIally is some admixture of tho
 capping under the plan observed, but
 after all it's a question of profits
 more than of conservation at thi'
 point.
 A Fig Tonnage ot Broken Ore In the cutting up and settling O
 the deposit there has been sufficien , time to deyeiCp a surplus in excesi i uf the d.,ily requirements for thu , crushers and the mill. We judge ther' , are a couple of million tons of Or' new in the mine ready to be drawn As the daly shipments amount C about 500 tons, it will be seer that very few men could handle the ton maze that would he demanded lo maximum production for a period o
 over two-thirds of year. In othe , words there is enough ore brokei
 in the mine today to furnish the mil { all it requires for the foreg ing lengt
 cf time. This tonnage can be increase
 steadily as the work of cutting Il { and settling the ore body proceeds }. There might be some advantage | Q having this reserve in the case 0 |. trouble with the mining force, whic }. Is improbable.
 Q The Quality of the Ore r The run of the mine, so we wer
 told, gives about 2.l7 per cent coppe
 per ton. We are informed that thi Y nets about 1.75 per cent in the ma V processes. which, with the cost o' h taiEed here, should yield a very han' ,f some profit. There is skilled handlin a cf material everywhere so that tn if cost must be under the general ave e age. It is safe to say that no othe V property in any field is securing be t ter mining costs. There are man '' things to suggest this condition. Is The Ray Central ore is of hight n grd e, and considerable coarse ore l. selected here that goes direct to tn Is smelte:.
 e How Trains Are Hauled it Or the motor levels there are fiN }" tons cars used. The electric motol
 handle trains of about fifteen cal q. each. The train is run to the moui t. of the level and backed upon tippI l. or revolving crdle. where three cl Is re dumped, the trin being uncouple rs to permit this. The empties it pushed bck nd three more cars al ID SO on until the train Is all unlcade m when the empties are kicked baC le upon a siding and handled out to u ss filing chutes again. The simple a D. engagement works smoothly. Vel ,k coarse ore Is broken in the car le where it shows, by siedse by a mi Is in attendance at the tipple. and aft h' dumping it goes on coarse rt nt screen where the very large piec IS are caught and broken by hammeriI d with, sledge or bar.
 ie crushers Located in Headframe up Shafts are two-ccmpartments, WI as iron guide, ten-ton skips working U, balance Skips dump the ore to DOC - cts that feed Gates gyratory crushe ", built in the headframe. Ore first go 1u over woven steel round rod screer
 which take the place of the ordina ~ grizzlies. From the crushers the bl - ken ere is elevated and dropped dev " " to the rolls where it is broken in m ,5ne-inch size. There are only u -, one set of crushers and one set ls rolls, and we observed that the fin yb were plentiful, probably due to | or fact that the ywere carried arou an the rolls many times before being ,s leased. Hoists and other machine to here Is actuated by electricity, pow