. Transactions. Fig. XI. -A Dirticuli Set-up 4i6 The Canadian Mining: Institute. 27 men, working 9 on a shift. They were getting $59 00 per foot forthe entire work, doing their own driUing, blasting, and timbering inorder when ready. They were using two sinking buckets. Under thecontract system the average wage rose from $ to $ per difficult ground a miner may still choose day wages. BLASTING. As the result of blasting is the aim of drilling it is of course essen-tial that all holes be of such a length and so placed in both positionand direction as to accomplish a clean break wi
. Transactions. Fig. XI. -A Dirticuli Set-up 4i6 The Canadian Mining: Institute. 27 men, working 9 on a shift. They were getting $59 00 per foot forthe entire work, doing their own driUing, blasting, and timbering inorder when ready. They were using two sinking buckets. Under thecontract system the average wage rose from $ to $ per difficult ground a miner may still choose day wages. BLASTING. As the result of blasting is the aim of drilling it is of course essen-tial that all holes be of such a length and so placed in both positionand direction as to accomplish a clean break with a minimum of ex-. Fic. XII.—The Ore Skips at the top. plosive. The respective arrangements differ in drifts, raises, andslopes. Cartridges of about \ diam., \o long, made of nitro-glycerine packed in sawdust or cornmeal, 40 to 70 per cent being nitro-glycerine, are used. The paper wrapper is slit, cartridge thrust in drillhole, and packed lightly with a wooden rod. Holes run usually from3 to 7 feet, and explosive required is proportional. Wrapping paper if ii The Le Roi Aline. 4»7 at hand and necessary is used for tamping. Forty per cent, powder isused where rock is easily broken, stronger where it is harder. Thecombustion cap of a six foot fuse is thrust into the centre of the lastcartridge. After all the holes have been thus charged, the fuses are cutso as to time their explosions by their lengths. This requires care andexperence. The holes must break in an order. They must, of course,always break towards space. In drifts the cut holes break first, blast-ing out a wedge ; the breast holes follow,
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Keywords: ., book, bookcentury1800, booksubjectmineralindustries, bookyear1895
