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The stono-breaker used is one of Blake and Marsden's, which gives every satisfaction. It crushes five tons of ore per hour, reducing the ore so that the largest will pass through a half-inch mesh. The pulverizer is one of Lucop's, which is a good pulverizer, but the wear and tear on the gudgeons and small roller are very great, and consequently very expensive to keep in repair. This pulverizer is capable of reducing the material that comes from the stone-breaker at the rate of 1|- tons per hour fine enough to pass through a mesh of sixty holes to the square inch. The jigs are entirely of a different construction from that commonly in use. They were designed by Mr. Warren, the mine-manager. Instead of a plunger forcing the water up from below through the bed of coarse ore on the sieve, the sieves move up and down in a tank of water. The tanks are made in three compartments, so that the ore can be deposited in three different grades. There is about 4ft. 6in. in depth of water in the tank, and the sieve that forms the jigger is made 2ft. wide, with the sides standing up 6in. above the bottom. There are cross-bars of iron placed on the upper side of the sieve crosswise, at intervals of about Bin., to keep the bedding or ragging of coarse ore in its place. In the spaces between these cross-bars there is a ragging of the heaviest ore, broke into pieces of ljin. in diameter. The crushed material is carried from the pulverizer in a chute on to this sieve, to go through the operation of jigging. This is accomplished by means of cranks and two rocking-shafts, which give the sieve a plunging motion and also a jerking motion, throwing the gangue towards the lower end of the_ sieve, while the particles of greatest density pass through the first portion of the ragging and sieve into the first compartment of the tank. The next greatest density goes into the second compartment and into the third, while the gangue and slimes go over the end of the sieve into a chute, and are carried off. This description of jigs works very well, but there is still a great waste of material after leaving the jigs, as a large portion of the ore is bound to be carried away with the slimes. The manager is aware of this, and wishes to have other concentrating-machinery placed at the end of jigs to treat this material. The same class of machinery that is used for dressing tin-ore is applicable to dressing antimonial ore, and a Bittinger shaking-table would be a suitable machine to treat these slimes. These tables are' about 9ft. in length and about 3ft. in width. The material enters these inclined tables on one corner, and, the water being continually flowing over the whole table, the shaking motion, which is in a rectangular direction to the incline, throws the down-running material into the current of water. The heaviest parts advance most, and when the material arrives at the lower end the current is divided, and the material passes into different receivers. The, action of these tables can be regulated, according to the character of the material under operation, by means of altering the incline, the quantity of water, and also by the length and form of the rectangular motion, which is adjusted by steel springs. These tables work automatically, requiring no manual labour. After leaving this shaking-table the finer slimes are treated on convex rotating buddies, which are from 12ft. to 16ft. in diameter. All the slimes are fed into a receiver at the centre. The buddies, revolving slowly, are supplied with jets of clean water at different points, so as to insure perfect concentration. The lighter particles are washed off and become waste, while the heavier particles remain on the convex surface until washed off into a receiver. The whole of the machinery is driven by a Telton hurdy-gurdy -water-wheel, with 2£in. nozzle, under 76ft. of a head. Smelting-works. — The smelting-works consist of three furnaces—-one furnace for treating the crude ore and two furnaces for smelting the ore in crucibles. One of the smelting-furnaces is made with a large firebox, for using firewood. The flames pass over a bridge into a furnace about 4ft. in width and 20in. in height to the centre of the crown of the arch. On the crown there are two rows of circular openings, seven openings in each row, which are provided with firebrick covers bound with a strap of iron. Into each of these openings a crucible, containing from 301b. to 401b. of ore and flux, is placed, and allowed to stand there until melted, which takes from one to two hours, according to the quality of the ore under treatment. When it is melted the crucible is lifted out by means of a tongs, and the contents run into conical moulds, and is known as the Singling Process. —When the ore is rich it is broken up to about lin. in diameter, and put into a red-hot crucible with flux obtained from the slag of the second or doubling process, and also a certain quantity of scrap-iron, being generally the waste clippings of tin plates and old tinware. The amount of iron required for flux depends on the quality of the ore to be smelted. If the ore contained from 50 to 55 per cent, of antimony, 401b. of ore would require from 161b. to 181b. of iron. The richer the ore the more iron it requires. The quantity of ore usually in each charge in the crucible is 351b. This will give on an average, with the ore that is now being smelted, from 121b. to 151b. of metal. When the metal and slag which was poured into the conical mould is sufficiently cool it is emptied out and a little water used to cool it; then a blow from a hammer will break the slag clean off from the metal. The metal being heavier than the slag, it settles at the bottom of the mould, leaving the refuse on the top. Doubling Process. —The singles, or metal from the first process, is sorted, so that the singles that contain an excess of sulphur may be melted with those having an excess of iron. This is put into a crucible, with a little salt-cake (crude sulphate of soda) and slag from the drenching or refining process for flux. In the furnace where this process is conducted, each opening where the crucible is set into has a fire-grate of its own. These openings are about 16in. in diameter, and about 3ft. deep to the fire-grate. There is a flue near the top of the opening, which connects with a main flue running along the side of a number of small furnaces. The metal is broken up and mixed with very rich ore, if there is any, and for every 601b. of metal about 21b. of salt-cake is used and 41b. of slag from the refining or Frenching process. The crucible is set on a coke fire, after which there is a cover, in shape of an inverted bowl, set over the" top of the crucible, and afterwards filled round with coke. This is subjected to a strong heat for an hour or an hour and a quarter. When it is melted the crucible is then taken out and the molten mass poured into cast-iron moulds; hence the metal gets the name of bowl-metal. 7—C. 5.