17

C—3

Shafts. —No. 2 shaft : Two chambers have been excavated at No. 0 level, and the pillar of ground under No. 8 level has been removed. No. I shaft : The west compartment lias been sunk a further MJft.. having also been enlarged to 8 ft. 1 in. by 6 ft., making the total length of the shaft HU ft. by 6 ft. wide below No. 9 level. No. 5 shaft: This shaft was sunk from 32 ft. to 152Jft. below No. 9 level, making a t<itiil of 1,156 ft. from the surface. No. 10 level chamber has been excavated, also a cistern for the B and C pumps. The C pump draw-lift was built in from No. 10 level to No. 9 level, and the B pump plunger is being erected from No. 10 to No. 9 levels. No. 6 shaft : This shaft has been sunk to a total of 1,023 ft. from the surface ; ft. was sunk during the year. A quartz hopper 9 ft. by 8 ft. by 140 ft. has been excavated from No. 9 to No. 8 levels. Approximately 252,428 short tons of material have been obtained from the cuttings on the surface and from deadwork crosscuts underground for filling in the depleted stoping-areas. There are nine filling passes from 600 ft. to 851 ft. in depth. The total quantity of water raised during the year was 556,731,024 gallons, of which the B pump raised 24,698,624 gallons, and the C pump 532,032,400 gallons. From the Ist October to the end of the year the water was raised from the 1,150 ft. level. The total quantity of ore crushed during the year amounted to 442,020 tons (dry weight, of 2,000 lb. per ton), exceeding the total of the previous year by 25,207 tons. The ore was obtained in the following proportions from the reefs worked during the year: Martha, 226.442 tons ; Empire, 63,165 tons ; Royal, 51,860 tons ; Welcome, 46,501 tons ; Edward, 45,601 tons ; Regina, 5,841 tons ; Princess, 1,198 tons ; H lode, 613 tons ; Victoria, 423 tons ; Alexandra. 360 tons ; No. 2 reef, 16 tons : total, 442,020 toiis. The product was 1,192,094 oz. of bullion, exclusive of concentrates, scrapings, concentrates slag, slag tailings. Victoria mill scrapings, and copper-lead bullion. During the year 711,623 tons of concentrates were treated at the concentrates-treatment plant at Victoria mill, producing 332.841 oz. of bullion, valued at £160,775 4s. Tterluction-works. —The tonnages crushed at the three mills, together with the tonnages crushed during 1909, were as follows : Waihi mill (ninety stamps) and average of 3-7-1 tube mills full time — 1909. 119.065 tons: 1910, 119,619 tons. Victoria mill (200 stamps) and average of 8-17 tube mills full time—l9o9, 273,917 tons ; 1910, 290,655 tons. Union mill (forty stamps) and average of 1 tube mill full time—l9o9, 23,831 tons ; 1910, 31,746 tons : total—l9o9, 416,813 tons ; 1910. 442.020 tons. Increased tonnage for year, 25,207 tons. The total average number of stamps running during the year, exclusive of Sundays and the Christmas holidays, was 294-908 out of 330 stamps. The total average duty per stamp per diem was 5-013. representing an increase of 0-521 ton per stamp compared with the previous year. The respective figures for the past five years are as follows : 1906, 3-504 (daily duty per stain])) ; 1907. 3-794 ; 1908, 4-167 ; 1909, 4-492 ; 1910, 5013. Waihi mill (ninety stamps and five tube mills—the fifth mill started in May) : A single-compart-ment wash-tank for No. 2 slimes was erected in ferro-concrete, and the vacuum-filtration frames increased, so as to handle 50 per cent, more slimes. Four ferro-concrete agitator-vats, 13 ft. in diameter by 55 ft. high, have been erected to cope with the increased slimes. Two electric motors, 250 and 100 horse-power respectively, to utilize power from the mine electric generating-station, have been installed. The 250-horse-power motor is for driving the tube mills, replacing the steam-engine formerly used, and resulting in considerable economy. The 100-horse-power motor was installed at the slimes-treatmentjplant. An additional tube mill, making five in all, was installed, and commenced running in May. A second Davey pump, formerly used for pumping water for general mill-work, was installed to pump slimes to the tall agitators. An air-compressor, made at Victoria mill workshops, was installed to supply air to the slimes agitator-vats. The total rainfall for 1910 amounted to 101-07 in., being 16-02 in. above the average of the previous ten years. Victoria mill (200 stamps and eleven tube mills—the eleventh started in August) : Twelve more concrete-bottom agitator-vats, 60 ft. high by 13 ft. diameter, placed on a concrete foundation over the tail-race, are being erected. Retaining-walls of concrete were built to support the tail-race embankments. The electric cranes in the slimes-treatment plant have been fitted with magnetic brakes, resulting in fewer stoppages in the plant. The heavy flood on the 29th March caused a total stoppage of this mill for thirty-six hours, the flood-water rising to a height of from 2 ft. to 5 ft. in the machine-shops, gas plant, offices, &c, causing damage toTnachinery, and carrying away a. considerable quantity of coke, coal, and timber from the yards. The main boilers have been fitted with steam blowers for improving the combustion of slack coal. A Heclon breaker and an elevator have been added to the stone-breaker section. The Government railway-line has been extended to allow for extra storage of coal direct from the Government trucks. Producer-gas and tube-mill plant : The 250-horse-powerJtandem gas-engine was started in February, and is a decided improvement on the opposed cylinder type. Considerable economy has been effected by the use of a proportion of slack coal in the producers. Union mill (forty stamps and one tube mill) : Withjthe exception of a bucket-elevator to lift the slimes-pulp from the disintegrator to the agitators, there have'been no additions to this mill. Air-samples. —Samples of the mine-air were taken in the warmest working-faces in this mine with the following results : No. 10 level—Temperature, 80° dry, 79° wet (Fahr.) ; carbon-dioxide, 0-28 per cent. ; oxygen, 20-83 per* cent. No. 9 level, Reptile crosscut, off Royal lode —Temperature, 85° dry, 84° wet (Fahr.) ; carbon-dioxide, 0-37 per cent. ; oxygen, 20-30 per cent.

3—C. 3.