WARREN AND MAY'S PATENT. ORE DRESSER.

Thames Advertiser, Volume VIII, Issue 2021, 16 April 1875, Page 3

WARREN AND MAY'S PATENT. ORE DRESSER.

Oub readers will doubtless recollect that a few weeks back we gave a description of a new ore-dresser, the joint invention of Captain John Warren, of the Parramatta mine, and Mr Frederick May, of the Phoenix Foundry, Crawler. Messrs Martin and Co. have just completed one of these machines, being the fourth they have made, for exportation to New Caledonia. The machines already in use are highly spoken of for the cheap and effective manner in which they do their work, and are said to be a great improvement upon the old jigger. It is proved by experience that by the new dresser ore can be cleared at the rate of per ton, or about one quarter the cost of the old method. .Any one who is practically acquainted with tlie jiggers hitherto in. use will know that the power was very unevenly distributed over the si"ve, if the "stuff" to bo operated upon came in rather quickly it would accumulate at the top of the sieve, and consequently offer greater resistance to the water, thereby driving all the motiou to the tail end of the sieve, where it was touch le.«s required; if, on the contrary, the stuff came in slowly, the stuff would gather at the lower end, and the motion be mainly con. fined to the front. The new dresser obviates this by having the hutch divided into five separate water-light compartments, thus giving a uniform motion throughout the length of the sieve. Another great objection to the old jigger is, that the suction caused by the return strokes of the plunger draws the water through the sieve, and in doing so alas draws a quantity of fiao saod ; &c., into the hutch with the oro. In tlie new machine this is quite done away with, a number of valves being provided corresponding to the openings in the hutch, and opening downwards under the plunger through which all the water necessary to give the required impulses can pass. The patent dresser also empties the refuse by a self-acting apparatus, and by means of a valve any " ragging" that accumulates in the sieve is at once got rid of. These two last, improvements save at least the labour of one mfin. The new dresser is capable of making from 170 to 200 strokes per minute and will get through from six to eight tons per hour in a much more effective manner than the old machine. The machines already in use have given great satisfaction, and we have little doubt that' they will soon be iu general use. Mr May informs _ua - that they would be very effective, in riddiug gold crushings of the pyrites, which have been so long a stumbling block in the Victorian and other gold districts.—Bwyip (6,A.).