C.—2.

the principal operations were carried on last year is a conglomerate mass of quartz stringers and sandstone, 10ft. thick in places ; but there are no regular well-defined walls. There were 1,138 tons of lode-material crushed last year, which yielded 780oz. gold. A large amount of gold has been obtained from this claim since it was opened, but the gold-bearing reefs do not appear to extend far in this neighbourhood. Waihi Mine. —This is the property of an English company termed the Waihi Gold- and Silver-mining Company, who have been employing about sixty-five men, and have erected a very extensive plant for the reduction and treatment of the ore. The plant consists of four dryingkilns, one of Howell's revolving furnaces, two sets of rock-breakers, one set of smooth-faced rolls, with revolving screen with steel tires, two Globe ore-crushers, four McKay pans, eight combina-tion-pans, four settlers, and one clean-up pan, and two sets of elevators. The ore, as it comes from the mine, is dumped into the drying-kilns, and while it undergoes the process of drying it is partially calcined. These kilns are of a circular form, resembling a limekiln. The ore is taken from these kilns to the stone-breakers, and there reduced to about fi». diameter. From there it goes into a hopper which feeds the rolls. The rolls are made on the Krom principle, of 26in. diameter and loin, face, having steel tires 3in. in thickness. They are driven at a speed of eighty revolutions per minute. Underneath the rolls there is a chute into which all the crushed materials fall, and this chute conveys it into a revolving screen of thirty-six meshes—which is equal to nearly 1,200 meshes—to the square inch. What will not pass through the meshes in the screen falls into a chamber and is lifted with a set of elevators into the hopper feeding the rolls, and is again put through. The crushed material from the rolls is taken to the Globe crushers, and there pulverised to such a fineness that it will pass through a screen having about 2,500 meshes to the square inch. The Globe crushers are 3ft. in diameter, with a steel ball of Bin. in diameter. The revolving disc of the mill makes 250 revolutions per minute, carrying round the ball with it, the ball being held in its path by a half-round groove in the cast-iron casing. On each side of the revolving disc screens are bolted on to the casing, and from the discharge-openings the finely-pulverised material is drawn by an exhaust fan through a square box or tube into a system of pyramidal chambers having numerous divisions. The object of this pyramidal or V-shaped chamber is to cause the fine dust to take a serpentine course, to allow it time to settle in the chambers, on the same principle as chambers for condensing fumes. The next process is to take the finely-pulverised material from the pyramidal chambers to the Howeli revolving roasting-furnace, where it is operated on. After being roasted, the ore is taken to the combination-pans and treated in them. These pans are sft. in diameter and 3ft. deep, having a revolviug muller fitted with chilled hamiatite-iron shoes, and dies of same material in the bottom of the pans. Each of the pans is charged with 3001b. of quicksilver and 1-J- tons of ore, with sufficient water in the pan to convert the material into a thin pulp. A cover is bolted on to the top of the pan and the muller set in motion, the ordinary speed of which is from seventy to eighty revolutions per minute. The water is heated in the pans by a steam-jet to a temperature of about 180°. A little salt and sulphate of copper is used in each charge according to the character of the ore. The mullers are kept working for about seven hours, when the whole of the bullion is supposed to be amalgamated. A tap is opened at the bottom of the pan, and the pulp and quicksilver runs into the settler. There is a settler for every two combination-pans, and things are so worked that the two pans are discharged into the settler at the same time. The settlers are 9ft. in diameter and 3ft. deep, having a revolving arm, with shoes, to keep the pulp in a state of agitation. The shoes do not touch the bottom of the settler, but stand a short distance above it. This arm is made to revolve at the rate of seventeen revolutions per minute, and the settler is kept working until it is required for the next charge from the combinationpans. Each settler is fitted with a siphon for drawing off the quicksilver. When the settlers are cleaned out ready for another charge the quicksilver and amalgam is run into a straining-cloth made of canvas, which is held in position by a wooden frame directly over a cast-iron tank, into which the quicksilver filters, and from which it is again lifted to charge the combination-pans. The whole of the machinery is to be worked by a semi-portable compound steam-engine of the under-type make, with multitubular boiler, the cylinders of the engine being 15in. and 24in. in diameter respectively. The revolving furnace was not erected at the time of my visit; neither had the mill done any work. The whole of the machinery is fitted up in a good workmanlike manner, but the arrangement of the plant does not do credit to the superintendent : there is by far too much power lost in lifting and elevating the material from one process to the other, and that power will be expensive, especially where steam is used, on account of the cost of fuel. The plant, no doubt, should have been placed in such a position that the ore could be run directly to the rock-breaker, and from thence by gravitation to every other process that it has to go through, so as to economize labour and motive-power. The Globe mills erected here are new machines in the colonies ; but it is very questionable if they will prove economical crushers, judging from the one working at the Melbourne Exhibition. They require a large amount of power to drive them, and the wear-and-tear on the balls and casing must be very great. The Waihi Company's plant has, however, many good points about it, and will certainly save a larger percentage of the bullion than was formerly done. It has cost about £12,000. A shaft has been sunk to a depth of 130 ft., and a pumping-and-winding engine erected. About 2,400 tons of ore has been stoped out of the upper adit-levels, and stacked on the surface ready to be operated on when the mill? is in full working-order. This ore has been all assayed by the company's metallurgist, Mr. G. W. Small, and its value is estimated at about £10 per ton. As soon as the machinery is in full working-order a new level will be constructed from the shaft, to give about 100 ft. of backs on the Union Eeef, which is from 4ft. to sft. in thickness. Parcels of stone

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