ATMOSPHERIC QUARTZ CRUSHING MACHINES.

Tuapeka Times, Volume III, Issue 159, 23 February 1871, Page 7

ATMOSPHERIC QUARTZ CRUSHING MACHINES.

A trial of a quartz crushing machine — one of the " Patent Atmospheric Stamp and Quartz Crushing Machines," manufactured by Messrs. Young and Co., at the St. Leonards Works, Perth — took place -on Saturday, 11th Feb., in Great King street, wherein the

machine, had been temporarily put together. The machine is owned by Messrs. Bright Bros., and Co., who act as agents for the manufacturers. It is driven by a five horse-power engine. The stampers used weigh each about 751bs. The piston a.nd stamper — the top of which acts as piston rod — are raised by cams on the main shaft. The action of these cams is so arranged that one stamper is depressed while the other is raised. The blows being given alternately, the main shaft is thus rendered equivalent to a balance wheel. The piston rising with the upward motion of the stamp causes a vacuum in the chamber in which it works. When the stamp is freed of the upward motion of the cam which raises it, the pressure of the air on the piston gives so great a downward momentum to the stamp, which weighs about 75 pounds, that it strikes a blow of nearly 1000 pounds. Each stamp at average speed strikes 150 blows per minute, and as it rotates with its own motion, it of course wears evenly. In this particular machine there are two stamps, but the principle upon which it is constructed allows of one, two, or more being driven upon the same shaft. As one stamper is raised whilst the other is depressed, a separate air-chamber is of course required for each. On Saturday, the stuff put through was dry crushed. The quartz, as fast as it was beaten into dust, was blown, by the action of a fan, through a pipe with an upward bend, which prevented the larger particles being carried away till properly

pulverised. Attached to the machine is a cradle which works backwards and forwards, in this quicksilver is deposited, and a stream of water passes through it. The mouth of the pip • is immersed in water, through which the dust is blown. The machine can, if so desired, be arranged for web crushing. Its weight complete is a little more than a ton, and this, with the fact that it can be easily taken to pieces, renders its transport economical, so that if a reef is worked out, or has been unproductive, the machine can be easily transported to another. It is claimed that a twostamper machine such as this will do the work of an ordinary 8 or 10 stamp mill, and that it, owing to the fineness to which it reduces the quartz put through it, save the whole of the gold, and that it will crush from four to eight tons per day, according to the degree of fineness required. — " Daily Times."