Douglas Island news., 1903-11-04

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 sary were it not required as a support for the skip-guides, ladders, pipes, etc.
 All shaft-sinking is done by contract, and if possible the contract for all work on the lowest level and for the shaft is let to the same parties. These contracts include the sinking, hoisting from the shaft, driving of shafts, tram ming, etc; or, in other words, the com pany furnishes steam, air and tools, and there it's liability ends. Two machine drills are usually employed for sink iug. Two sizes have been tried, and the larger, or the new Ingersoll-diame- ter of cylinder, 35S in.--has been found superior to the 3A in. machine formerly used. The rock is quite hard, particu- larly on the hanging wall side of the deposit, and it has been found that the number of feet drilled with the large machine is fully 30 per cent more than with the smaller one.
 Both 10 and S-hour shifts were tried, and the best progress made with the former; consequently, all shafts, as we'll as other underground work, are done by 10-hour shifts. The center-cut system of drilling is employed. The cut is first drilled, blasted and mucked out, then the other holes are drilled and blasted and the dirt removed in the usual manner; save that the end holes are reserved, and fired with the cut-holes of the following round.
 Although the shafts vary from TOO to 900 feet below sea-level, and one of them is under the channel, very little water is encountered in sinking. Most of the water in the mines comes from the surface, and is caught up and pumped out, usually from the first lev el. The water underground does not average over 30 gallons per minute, and this is handled either by the skips or by No. Cameron sinking-pumps. Cross-head and buckets are used for sinking. The bucket is flst-bottomed, with the sides projecting 2 inches, thus giving it more secure base and per mitting it to remain upright on an un- even surface while being filled.
 The question of light at the bottom of shaft has always been vexatious one, owing to the water and blasting; but this question has been solved by using group of three 36c. p. electric lamps in the place of torches or can dies. The wire is brought down the shaft to some convenient point, where a small reel is placed with which the lamps can be lowered or raised at will. It has been found that the best wire to use is the ordinary lamp-cord, wrapped with heavy canvas and given a good coat of P. & B. paint.
 At the Ready Bullion mine the ore- body lies for the most part under water. For this reason vertical shaft would be impracticable; therefore an incline shaft was started at point l60 feet from the footwall and sunk at an angle of 47 degrees 53 min from the horizon tai. To protect the underground work ings from the sea, pillar 300 feet thick was left in place above the highest workings in the main ore-body of the mine. The ore was cut at distance of FPS feet along the incline, and the shaft continued to the 750 foot level. In the meantime the footwall had become much sleeper, and it was evident that if the shaft was continued at the same angle, it would soon be out of the ore. The shaft was then gradually steepened until at the 900 foot level it has an in- clination of 80 degrees, and the shaft continues at this angle to the next lower level.
 STATIONS AND ORE E-B1Ns-Formerly it was the custom to open up level every no feet, but below the 440 foot level, the distance between levels in the Treadwell will be 15O feet from now on. By this method large development expense will be avoided.
 At each level station is cut out, the width of the shaft, from 40 to 60 feet long and with an average height of 8 feet. In the Treadwell the main cross cuts run parallel to the wall, plates of the shaft, and as far as possible it is aimed to have the station on the side opposite from that toward which the skips dump. When the station-level is reached in timbering the shaft, sta tion set is put in. This set is 14 feet high. and is tied in two diractions by