Zinc Mines. In the vicinity of Chelmsford, Algoma, near Sudbury, are indications of zinc, which Ore in Gra- may prove to be of some importance. phitic Slate. These occurrences seem to have some connection with the graphitic slates, associated with which are also found the deposits of anthraxolite, which have been discussed in former reports of the Bureau of Mines. Balfour Zinc Mine. The work The location of this property is on lot 7, first concession of Balfour, Algoma, four miles southwest of Chelmsford. It is owned by George Bennett of Toronto, and was being developed on option by J. G. Mills of Chelmsford, and John Dobbie and Leonard J. Lawrence of Niagara Falls, New York. About 300 tons of ore had been extracted, said to show by assay.45 per cent. of zinc, 0.76 oz. of gold, and 9 oz. of silver per ton. ings consisted of a development shaft, 7 feet 8 inches by 9 feet 10 inches crosssection, and 98 feet deep, sloping 75° to the south. It was timbered by a collar with timbers laid "skin to skin" to a depth of 9 feet 9 inches. Below that the walls were sound enough to stand untimbered. Hoisting was done by kibbles on a skidway, with a horse-whim. Objection was made in this case, as in all others, to the use of kibbles on skidway in shafts of any considerable depth. Some minor recommendations were also made regarding platforms at the shaft mouth, and idlers for cable in the shaft. Dynamite was suitably stored at a distance from the shaft. A manway was provided with platforms every 40 feet. It was ordered that the manway should be partitioned off from the hoisting compartment. Date of visit, August 12, 1898. · 11th Bottom of haft. Hoisting is done at present only from the tenth and eleventh levels. All necessary precautions for safety in the shaft have been taken, except that the signal code was not posted below ground. This was ordered to be done. The old shaft on the 43° angle had been carried down to the seventh level. This is still kept open, and the manway is maintained in a suitable condition to serve as an alternative means of exit. The manway in the new shaft is also kept in excellent condition. The stopes could not be remeasured without making rather elaborate preparations, and Stopes of consuming much time. The dimensions according to the former Inspector and according to records in the office of the Company are given in parallel columns. the Mine. In the eleventh level stope the "back" or floor arch for the tenth level floor is intact. A winze from the bottom of this stope extends 40 feet downward, and from each end of the stope are drifts, one on a N. W. course 42 feet long, with cross-section 8 by 8 feet, and one on a S.E. course 100 feet long, with the same cross-section. Diamond drill holes are carried ahead of the workings as the breasts advance. The tenth level stope has been carried up to the eighth level through the removal of the intermediate "backs" or floor arches. The walls are nearly vertical, there being but a slight over-lie of the hanging wall. This wall has support from a buttress of rock or ore in place near the middle on the hanging wall side 18 feet thick by 30 feet high. No mining was being done on this level, but the accumulated ore from the broken-down floor arches was being removed. The old cross-cut from the shaft to what was formerly the ninth level stope has been closed by a gate. The eighth level stope has also been carried up by breaking through floor arches to the third level, but does not constitute part of the stope from the third to the second levels. The floor arch on the eighth level is 40 feet thick, the span being 30 feet. Gates were ordered placed in the cross-cuts from the shaft to the eighth and seventh levels. An arch has been left spanning the stope about six feet below the floor line of the seventh level cross-cut, giving a support at this point Scaling The floor arch of the third level stope has been broken through into the lower stope at only one place. There is also a winze from the top of the stope which has been carried up to the surface. The first level stope has been broken through the surface, so that it now constitutes in part an open pit. At the N.W. end of this pit a drift is being run towards an old prospect shaft 75 feet beyond. This is the only mining now Condition of the passage. from the old shaft. in progress above the The mine is kept well drained and clean. Only one day's supply of dynamite is kept underground. This is stored in a the Mine and locked magazine in the old fifth Works. level cross-cut, completely blocking It is warmed by a steam pipe Explosives are lowered on the first skip down after the noon hour. before the miners return from dinner, being received by a man specially appointed for this purpose, who is the only person in the mine at the time. Ventilation is excellent, except in the upper part of the manway, which is heated by the air from the lower part of the old shaft in which steam pumps are set. No changes have been made in the surface plant since the last inspection. The roast yards are conducted as in the past. Warning notices of danger are conspicuously posted at all approaches, and signals are given by steam whistles before blasting and after all danger is over. Roasting is done on contract by D. L. McKinnon. The only changes in the smelting plant consist in the erection of an extension eastward of the old furnace sheds to accommodate two new furnaces, making five in all. A new dust chamber and stack have been erected between the new furnace foundations, engine have been installed. The only advice and also two new blowers with a 50 h. p. given beyond that already mentioned was to submit to the Bureau of Mines plans drawn to scale of any proposed work affecting existing arches in stopes before undertaking their removal. Date of inspection, August 8, 1898. Evans Mine. The work done at this mine for the past year has consisted chiefly in the removal of floor arches and pillars down to the third level, thereby opening the stopes out to the surface as far down as that level. Stripping was progressing on the floor of the old third level at the time of my visit, and also on the west wall near the bottom. The lower stopes are full of water, so that nothing is known of their present condition. The shaft pillar has been stripped on the north side next to the stope from a point 40 feet below the surface to the bottom of the third level stope. Hoisting is done in kibbles. At the upper end of the shaft within the remaining portion of the pillar there is a cross-head, working in guides, which serves to guide the kibble into the shaft house. up A pit was being sunk about 40 feet s.E. from the shaft house, 25 feet in diameter, and 20 feet deep at the date of inspection. This was evidently endangering the shaft pillar, on which rested part of the foundations of the shaft house. Work at this point has been discontinued. No changes have been made in the surface plant. The trestle from the shaft house to the dump needed repairing, which was done during my visit. it was required that shaft timbering should be carried further down so as to admit of extending the travel of the cross-head nearer to the point of loading the kibble, which was also immediately done. Signal codes were ordered to be posted below ground, and further work affecting floor arches, beyond that then in progress, to be done only after the approval by the Bureau of Mines of plans for so doing. inspection, August 9, 1898. McArthur Shaft No. 1. Date of A The original shaft has been opened out, forming an open pit 103 feet deep, 70 feet long at the bottom, and eight feet wide. surface backing" or arch has been left 30 feet wide and 20 feet deep, to sustain the hanging wall. The dip of the vein averages about 80°. Hoisting is done by derrick and kibble, the cable passing over the rock house below to the winding engine house beyond. Ladders securely fastened to the footwall afford safe and easy passage for miners. One drill was working in the pit, driven by compressed air. Unwatering was done by bailing. A fence was ordered to be placed around the pit. Permanent mining at this point is not contemplated, a better location having been made 1000 feet s. E.. where surface stripping has been done preparatory to regular mining. A tramway with three feet gauge and 25 lb. rails has been laid connecting the new location with the McArthur No. 1 rock house. The cars will be operated by cable from the winding engine house before mentioned. Date of inspection, August 9, 1898. Preparations ent Mining. McArthur Shaft No. 2. The Work at this point is wholly new. location is about 3,000 feet north of the old Copper Cliff shaft. Extensive prefor perman- parations have been made here for permanent mining operations. The gossan has been stripped down to hard vein capping, and work on the new inclined shaft has begun. The shaft will be located within the country rock on the footwall side, the vein being reached by cross-cuts A rock house, designed similarly to those hitherto employed by the Canadian Copper Co., has been constructed 375 feet S. E. of the location of the shaft mouth, but on a much lower level so that the skipway above ground will incline only five feet in 100 feet to the dumping cradle at the head of a chute near the top of the rock house. The hoisting works are located at a still lower level beyond the rock house, and the cable will pass over a sheave on the upper framework of the rock house to reach the shaft. The installation of machinery in the hoisting works consis's of two boilers, 100 h. p. each, and two winding drums, five feet in diameter, actuated by engines with 12" by 15" cylinders. There is also an air compressor, capable of supplying power for 14 drills. A standard gauge railroad track has been laid from the roast yards to the rock house, 3,300 feet in length. In addition to the indicators for showing the positions of the skips during hoisting and lowering, it was advised that a registering apparatus be provided to record the signals transmitted to the engineer, and also to use detaching hooks with the necessary appurtenances to prevent overwinding, and it was recommended that plans of proposed supports for walls in stopes be submitted in advance to the Bureau of Mines as soon as sufficient exploratory work had been done to permit of so doing. Date of inspection, August 8, 1898. On September 26 a second inspection was made, by which time the new plant was in operation. Surface ore was being drawn to the rock house, and the shaft was under way. One Blake crusher was in operation, and a second was being installed. A dry house for miners had been fitted up near the shaft, and a suitable magazine for explosives was being built near the base of the hill below the rock house. As an alternative for the detaching hooks it was suggested that an automatic apparatus for shutting off steam from the hoisting engines in hoisting, and putting on brakes to the drum, might be employed. Extent of Stobie Mine. The shaft has been extended downward on a 60° angle to a fourth level. The depth on the incline from the third to the operations at fourth level is 65 feet; cross-secA double track second level, the Mine. tion 7 by 17 feet. for skips extends down to the carried and the north track has been down into the lower level. The shaft lies wholly within country rock on the footwall side of the ore body, 20 feet distant, the several levels being reached by cross-cuts. The cross-cut to the fourth level is on a curve, general direction w. of N., length 23 feet. The fourth level opens out directly as a large stope, 51 feet long, 43 feet wide, and 60 feet high. The stope is worked on two benches, or steps, the upper step being 45 feet above the floor of the level. The stope is being extended on ore toward the west and north. On the west side the ore face is being dressed at a point 20 feet from the eross-cut preparatory to leaving a pillar to support the hanging wall. An upraise, seven feet by eight feet, extends from the centre of the stope to the third level, being provided for ventilation. The third level also opens out as a stope, 78 feet long, 80 feet wide, and 70 feet high. It is likewise worked on two benches, and has an upraise to the second level for air. The dimensions of the second level stope remain practically as at the last inspection. The lower benches have been stripped back to win ore, and the upper bench has been worked back about 40 feet in a northerly direction, leaving a clean face which is to be cut around to form a pillar for the hanging wall. Access is had to this upper bench both from below and from above through an upraise to the surface, approximately 50 feet vertically. This was adjudged insecure and it was required that the upper part Instructions. of the upraise must either be cribbed and access cut off, or else it must be timbered down to the stoping chamber and ladders provided at a suitable inclination for ease in ascent, having a guard rail on the side exposed to the open stope. Drainage and ventilation in the mine were excellent. No changes had been made in the surface plant. It was further advised that the signal code should be posted at all loading stages below-ground, and that pillars for hanging wall should have a diameter at bottom of not less than 25 feet and at top of not less than 18 feet. It was also advised that in all cases when the span of a floor arch exceeded 20 feet the minimum thickness of arch should be 12 feet, and in no case should a less thickness than six feet be adopted. Plans drawn to scale were required to be submitted to the Bureau of Mines for approval before stripping of "backs or floor arches between levels 4 and 3, and 3 and 2 might be permitted. Other recommendations were made concerning blasting, indicators for engineer, and disengaging apparatus to prevent overwinding. Date of inspection, August 6, 1898. similar to that found in the other coppernickel mines of the Sudbury region. The work in progress consisted of three shafts. Shaft No. 1 was 20 feet deep, 12 by 9 feet in cross-section. It is timbered to a depth of 11 feet by hewn timbers set skin-toskin. Cross-section inside timbers 8′-9′′ by 6'-9". Shaft walls below timbers well trimmed and sound. Hoisting was done with an ironbound kibble and windlass, using 14-inch hemp rope. Water is removed by bailing. Shaft No. 2 had a aepth of 38 feet, cross section 13 by 8 ft. 7 in. Timbered to a depth of 11 feet same as shaft No. 1 Cross-section inside timbers 8 ft. 10 in. by 6 ft. arrangements the same as at shaft No. 1. At shaft No. 3 sinking had just begun. Shaft No. 2 is 500 feet E.S. E. from No. 1, and No. 3 is 650 feet s.s. E. from No. 1. Hoisting The surfact plant consists of a blacksmith shop 100 feet s.w. from shaft No. 2; a magazine for explosives about 400 feet from both No. 1 and 2 shafts, and 300 feet from No. 3 shaft, well built and guarded against danger from bush fires; a rock house on the north side of shaft No. 2, modelled after those in use by the Canadian Copper Co. The dimensions of the rock house at the base are 28 by 28 feet over all, and 50 high to peak of the roof. The pit-head frame for the shaft was being built adjacent to but detached from the rock house. The construction was massive and strong throughout. In addition there was an office, miners' quarters, and stable, all of logs, about 700 feet distant from all workings. Better windlass supports at shaft No. 2 were required, and it was recommended that the pit-head frame be given a broader base than was contemplated, or else that it be framed into the structure of the rock house to insure greater stability. Date of inspection, August 11, 1898. The owner is J. A. Powers of Lansingburg, New York, and the operators were J. A. Powers, F. A. Cheney, et al., the latter being also the resident manager. The ore body consists of a vein carrying mainly chalcocite, with some bornite and chalcopyrite, associated with a quartz gangue. The cobbed ore shipped to New York is said to contain the proper proportions of FeO and SiO2 to be self fluxing after roasting. Mine workings. The mine workings are as follows: A vertical shaft has been sunk 150 feet, cross section seven by nine feet, and six by eight feet inside timbers. Timbering is carried down as a collar to a depth of 18 feet. The walls below this point were sound and well trimmed. A manway was provided in proper form as to length and inclination of ladders, but was not partitioned off from the hoisting compartment. This deficiency was ordered to be made good. The first level is at a depth of 100 feet, drifting N. w. and S. E. from the shaft; crosssection 6 by 6 feet; N. w. drift 100 feet long; s.E. drift 25 feet long. The second level is at a depth of 150 feet from the shaft mouth. There is only one drift N.W., 75 feet long, cross-section 6 by 6 feet. There is one overhand stope in the 100 foot level, N. w., beginning 43 feet from the shaft; length 44 feet, greatest height 18 feet above the level roof, the width averaging about seven feet. Stulls eight feet long and 18 inches in diameter support "deads" on the first step above the level. These were not properly set, so that breakages of stulls were not uncommon when shooting down the face of the advancing step or slice. Instructions were given as to means for overcoming the difficulty. One winze had just been started under the middle of the stope downward from the 100 foot level. |