AN ATMOSPHERIC QUARTZCRUSHER.

Otago Daily Times, Issue 4144, 31 May 1875, Page 3

AN ATMOSPHERIC QUARTZCRUSHER.

The Kew Zealand Herald says :—The latest novelty in the quartz-mining world of Australia is a ] latent atmospheric stamp and quartzcrusher which was recently exhibited to the miners of BaUarat. This machine has iii less than a week, in consequence of its performances, commanded almost universal attention. It is a battery of two stamps, and weighs just one ton, and it does the work of seven or eight rtauips of the latest Victorian fashion. The main difference between it and the stampers now in use is, that while each of the latter, weighing 700 lbs, and falling by its weight at seventy blows a minute, strikes exactly at its own weight, the former weighs 75 lbs, and is made to strike with the force of 1000 lbs, striking at the rate of 300 blows a minute. The difference of result is the foUowing -.—

The old stamper strikes with a force of 98,000 lbs per mm nte, while the new one strikes with a force of 400,000 lbs. This convenient machine must be of immense benefit to prospectors as a crusher for everyday work. It may be described thus :—fiach piston and stamp-head, which rotate in the usual way, is raised by a double cam on the main shaft, thus alternating the blows, and making it equivalent to a balance wheel. The piston is raised into au atmospheric chamber, thereby creating a vacuum underneath the same, which gives immense momentum to the stamp when relieved from the upward motion of the cams, so as to produce the results above-mentioned. Tliis machine is said to be able to crush eight tons liar diem.