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Show DALY-WEST WILL OF HIGH TYPE Plant Is Interesting Because System Requires Use of Little Water. SHERMAN METHOD IS HERE DEVELOPED Eastern Journal Describes in Detail Plant of Great Utah Company. The D0.I7 "West mill ia particularly interesting in-teresting because it ia horo that P. Vf. Sherman doroloped his system of milling, mill-ing, ono fcaturo of which is tho small amonnt of water nsod, says tho Engineering Engi-neering and Mining Journal. Another prlnciplo is nevor to roject tailings until un-til they havo boon retreated nt least once. Jigs aro good coarso concentrators, concentra-tors, but ho docs not roject tailings from jigs. Mr. Sherman has also invented in-vented a systom of classifying tnnks, with which ho otrocts a close ejassificu-tton ejassificu-tton of pulp and treats each sizo on n separate table or slimor. Tho middlings from tho tables aro re-concentratcd on other tables or else sont back to the classifying system, because middlings from tho tables of this mill treating classified pulp aro duo not so much to attached fragments of lighter minerals as to the fact that the small grains of the heavier minorals wash under tho conrser particles of tho lighter, producing pro-ducing a middling band which can bo separated by re-treatment, without intermediate in-termediate crushing. The mill discharges no more water than is absolutely necessary to wash away tailings. It treats 400 tons of oro a day and discharges only '10 gallons of water por minute with tuilings, although al-though about 350 gallons por minuto aro flowing through tho systom. The overflow water from the classifiers is used as wash wator on tho tables, for jig wator, and also in regrinding the dowatercd jig tailings. By this method meth-od Air. Sherman effocts a saving of j ovor 95 per cent Pb (by wot assay), 75-80 per cent Ag., and about 50 per cent Zn upon an oro which averages 4.5 per cent Pb, 11.3 ounces Ag, and 5.2 por cent Zn. Much of the lost silver goes off in the zinc blendo and in the-silver the-silver chloride which occurs in the upper up-per levels. To make a high saving of zinc is not attempted at prosont, but another mill for saving tho zinc values is already planned and its erection is contemplated as soon as tho Ontario drain tunnel is reopened. The mill contains a number of novel devices, of Mr. Sherman's invention, which appear to be quite good. The springs that hold tho rolls up to their work aro kept under tonsion 'by a nut screwed up tightly against a aeries of nino rubber discs, ono inch thick, separated sep-arated by sheet-iron plates. These are compressed so that tho rolls aro rigid while crushing ore, but, if a piece of iron gets botwoon them they will open about 1 or 2 inches. Tho old typo of Huntington mill has been improved mechanically and by tho addition of now principles. Tho stem to tho muller rotates in an oil bath entirely protected pro-tected from grit and dirt. These stems now extend above tho yokes and aro connected with turnbucklos-and tension springs, whereby the mullors aro held lightly against tho dio ring. No attempt at-tempt is mado to increase tho capacity, but only to causo tho mullors to work smoothly against tho ring, for then they wear round instead of rough, as they do in tho old style Huntington mill. Then, too, in caso of any temporary tem-porary overloading, the tension in tho rods prevents choking. The Sherman classifier is an outside cylindrical tank with a conical bottom, insido of which is a stoel cvlinder whoso section nroa is just half that of the annular space. The insido cylin-'dor cylin-'dor is supported from abovo with its rim 6 inches higher than tho outside cylindor. The insido cylindor docs not extend 'down to the bottom of tho outside out-side oue. The pulp'is admitted to tho centor cylinder nnd passes down through a screen fput there to keen out sticks, etc.), thon up through tho annular space and overflows to a circular cir-cular launder around tho outsido of tho outer cylinder. This discharges to a simlar tank which has twico tho area of the tank preceding it. The Sherman table is an improvement improve-ment on the old Hooper slimer. It consisls of twenty-four trays, each 1 foot wido by 5 foot long, attached aide by side to form an endless belt which travels over sprocket wheels at each end. Tho first four of the trays are Kiven a bump and jar which tonds to throw tho material toward tho head of tho tray and also has the effect of stratifying tho material as in an old Gornisli dolly tub. Tho surface of tho belt is twisted, tho head ends of the first tniys being tho most olevatod, tho end of tho last tray the most depressed, de-pressed, whilo the middlo tray is level. Tho other seven trays of the top deck arc given a vanning motion which washes off the top of tho bed, stratified strati-fied by tho jarring motion of tho first four trays. Tho dovico which gives tho reciprocating motion operates in an oil bath nnd is placed above tho table ta-ble out of the way of anv splash. The trays have a piece of linoleum at their head ends, whore the feed pulp comes on, but tho bed of tho trays i3 lined with canvas. There aro two troughs under the discharge dis-charge ends of the trays, ono for tho middlings and the other for tho tails. Middlings come off the first two trays before stratification has been effected, and also off the last few trays when tho top lovers of tho bed aro being washed off. Tho point whero to cut out tho middlings is determined by panning tho tailings coming off tho different trays. Tho heads aro washed off tho trays by a jet of water coming from a perforated pipe placed under tho end of tho table. The method of keeping assay results at tho Daily "West mill is uuusual. Firo assays aro mado from daily samples of tho ore. A proportion propor-tion of each daily sample is kept for making up a weekly Bample which is assayed by the wet mothod. This sample ia made up by weighing out from oach dailv samplo tho proportion pro-portion represented by that day in tho wcokly run. The wceklj- samples aro j saved and combined in a similar way to mako a monthly sample, which also is assayed by tho wot method. These monthly sampleu then aro combined in 2 yearly Btmiplo, |