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Show How Asbestos is Mixed. Popular Science Monthly. . . Mining is carried ouoby cutting down the hills of asbestos-bearing serpentine, much as a farmer culs down a staek of hay and straw, or by open quarrying ou the level. The rock is blasted out aud the the asbestos separated from the containing rock, is "cobbed," that is separated by hammering from inferior forelgu matteri This cobbing is a comparatively com-paratively easy matter in the ease of the liner quality, as it usually separates readily from tho gunge, but iu the hwer grades much difficulty is experienced experi-enced in separating the fibrous matter from tho uou-librous. At best there is a great waste. Much of the asbestos is waste. Much of the asbestos is iu thin and narrow veins and is wasted, as by the present mode of operating it does not pay to Separate this from the serpentine. ser-pentine. A machine that will enable these narrow veins to be utilized is needed. When "cobbed" the asbestos is graded grad-ed according to purity, color and length of fiber into three grades and bagged for shipment. The finest quality or "firsts" finds ready sales at prices ranging rang-ing from $80 to $100 per ton; "seconds " fetch from $30 to $70 per ton; while "thirds" may be valued at $13 to $15 per ton. Iu good mines the yield of asbestos is from 3 to 5 per cent of the-rock the-rock quarried and the cost of niiuins: may be put down at $23 to $30 per ton. Returns obtained by the geological survey of Canada show that for tho year 1S8S Canada's output was 400 tous valued at tho mines at $'.)5,000, and this tho output of uine different mines. Over three fourths of the whole was shipped to the United States, small quantities going to Great Britain, Germany France, Belgium aud Italy and being used in domestic manufacturing. |