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Show SKLHCT r.i). SUCCKSSI.'Vl. APPLICATION OF MACIllNKllV IN MINING. Wo uso slcam cxlcn.sivoly in hoist-iiiR, hoist-iiiR, pulvcriziiiK tind concentniting ores; but hitherto huvo deicndej almost entirely en-tirely upon hnnd labor l'or running tunnels tun-nels and drills, and breaking down the ore. Tho Diamond drill tunnelling lnachino, however, has been tried at Smartavillo with success, and we may now consider it an important aid in the development of our mineral resources. It will boncet'ortli bo in constant and increasing use, unless superseded, aud that docs not now appear probable, by some suporior machine. Tho Ulue CI ravel hydraulic claim at Smttrtsville is one of'lho most valuable and best managed pieces of mining property in the Slato. It has yielded at least $1,000,01)0, and is expected to yield much mora. The company, while washing off the upper strati of the claim, have at tho same time been cutting cut-ting a deep tunnel through which to run off the lower strata. The lower tunnel was cut l,l?S.r feet by hand, at a cost of -lO,000, and three years labor. When in 1,200 feet, eight men were constantly con-stantly employed in it, .working in three shifts, and making about one foot in twenty-four hours at a cost of forty dollars per foot, blasting with black powder. The whole length of the tunnel tun-nel was to bo 1,5(53 leet, and as it would be an important point to hasten tho work, tho company determined to try the Diamond drill. A machine was made for them in this city on an original pattern, and after many delays incident to the introduction introduc-tion of a new method of working, the cipenuicui, is pronounccu a success. Fifty feet of tunnel have been made with it, and now that everything works smoothly and tho Company have sufficient experience to justify the expression of an opinion, tbey declare themselves satisfied. In the same kind of rock, which before cost $40 per running foot, with black powder for cutting the tunnel six feet wide and eight feet high, by hand, at the rate of one foot per day, they now cut from two to two and a half feet per day in a tunnel six feet wide and nine feet high, at an expense of $25 per loot. This price covers everything save the interest on the cost of the machine and the wear and tear. The power is supplied by a fifteen horse-power steam engine at the mouth of the tunnel, and is transmitted by compressed air through a hose to the drills, which bore holes an inch and an eighth ia diameter, at a speed of from half an inch to an inch and a quarter in a minute. The holes are usually from twenty to thirty inches deep, and all on the face of the tunnel are blasted out at the same instant by an electric exploder. The chief profit of the Blue Gravel mine, from the use of the machine, is in the saving of time. Tho tunnel, which has already cost $40,000, would be of no use for ten or eleven months yet if the drilling were done by hand, but with the help of the machine it will be ready for service io less than four months. Here is a saving of the interest on $40,000 for six months. Then tlie cuwpauy will got their gold dust from the mine six months, sooner and they will have so much more interest in-terest on that. They have other tunnels tun-nels to cut, and for the purpose of working to the best advantage they have purchased the machine now in use and ordered another. They authorize au-thorize us to say, that in their opinion, when the men have more experience, and when everything is arranged for the machine in the best style, it will do much better than at present. The success of the machine in this tunnel implies a success in any tunnel of equal size in hard rock. The larger the tunnel and the harder the rock, the greater the relative saving. We presume that there would be no economy econo-my in using a machine to cut a tunnel smaller than that at Smartsville, and that is larger than most of the mining tunnels need to be. Railroad tunnels are larger, and for them the machine is very valuable: Whether the diamond dia-mond drill could be used profitably in stopping or breaking down quartz rock, is a question upon which we are not prepared to express an opinion, but which is worthy of examination. Alta. |