QUARTZ CRUSHING.

Auckland Star, Volume VII, Issue 1975, 8 June 1876, Page 3

QUARTZ CRUSHING.

Some irontha ago Mr Thomas Russell imported from England some improved machinery for quartz crushing. In consequence of the depression in mining affairs, it was never employed, and has been lying in a disjointed state in a shed of the old distillery in Stanley-efcreet. Within the last few days it has b< ?n put together, and those interested in such things may now, by paying a visit to the deserbd spirit factory, see one of the latest English inventions for crushing ore aDd quartz. The machine is really nothing more than a two-stamper battery, but arranged on such a principle that it does the work of an eight-stumper battery of the ordinary pattern. The engine differs in two important particulars from those in general use. In the first place, the stamping action is derived directly from the crank shaft, which, as it revolves alternately, lifts and sends down each of the stampers. This idea is so very simple that it hag no doubt occurred to hundreds of persons before the inventor, but a difficulty has always stood in the way of its adoption, which was the danger of an unusually hard stone, or some unsmashable substance getting under the stampers, and causing the snapping of the crank or the shaft. The machine in question has this danger obviated by a clever contrivance which constitutes the beauty of the invention. Where the bearings from the crank are attached to the shaft or stamper rod, a cylinder encircles the latter enclosing a piston worked bodily into the shaft. There are two small holes in the cylinder above, and two more below the piston. It will thus be seen that the stampers, as they are lifted and sent down, are immediately moved by compressed air in the cylinders, and thus a kind of buffer is provided for any sudden jar or obstruction such as has been instanced. The substitution of the direct motion for that of the ordinary lifting and dropping by the aid of projections on the crank shaft enables the machine to attain the rate of about 150 stamps per minute, instead of 60 which is the highest speed hitherto attainable. The compressed. ai>-is also useful in heightening the force of each blow. The machins is interesting in other respects, but our readers, who are so inclined, can go and examine it themselves. We may mention that thi3 Etyle of battery hai been used for the last two years on the tin mines of Cornwall.