PATTERSONS ELEPHANT ORE STAMPER.

Te Aroha News, Volume I, Issue 51, 24 May 1884, Page 7

PATTERSONS ELEPHANT ORE STAMPER.

This now ore battery UuU fair to revolutionise, to some extent at lea^t, the moans of crushing quartz. A preliminary trial of a sample one took place at the Thames on Thursday, the 15i.h insfc., and I have seldom heard the opinion of experienced' men who ought to be able to pronounce a competent judgment so unanimously ' in favour of any innovation upon that to which they had been accustomed. The name <k Elep.iant Stamp," to my mind, is infelicitous, denoting as it doej Something ponderous, whereas in this instance the reverse is the fact, for the stamper is tiny .compared with the ordinary quartz mill. It probably is not more imiu six feet long, six feet high, and four feet broad. Indeed it does not appear much lurger than a piano. Cine of the lirst essentiafs is a strong foundation of concrete, stone, or timber. It. can be fixed in any convenient situation where Uero is a urivmg tuaft or v eel, and for prospecting purposes a 'oinaii buiAfiy can u« put to work in a

very short time, to bo driven by either horses or bullocks. Tne chief characteristic of this machine" is the small amount of power required to drive it, ami the entire absence df all waste, of impart, any excess of which when inadvertently applied heiiv* conserve! in the springs to which the hammer he" ads are attached. At the preliminary trial on Thursday the sp°B'l attained wnq ]90 blows ppr minute, and over half a ton of quartz >vhs put through ordinary grating in use on the field in 40 minutes" This would be equivalent to over 12 tons in 24 hours. The machine when properly ejected and with a sufficient supply of water should stamp from twelve to fifteen tons of hard and refractory quartz per 24 hour. I*,1 *, and of soft quartz a proportionately larger quantity, through a screen containing 1 900 holes to the square inch, if screens with larger holes are used, say 400 to the square in.-h, the quantity stamped would be correspondingly increased. The speed of the crank shaft should be 200 revolutions per minute, giving 400 blows in the same time. For Te Aroha, Ohinemnri, anil inaccessible claims, this stamper is Well adapted, as power could bo obtained from a small verticil boiler and engine combined, if water was not available, and for a total expenditure of about between £700 to £600 or so each chum Could crush its own stui at small costs, the stamper crushing so finely but little berdauing would be required. It should be mentioned that the stamp in reality consists of two stampers. The difference between it and tne ordinary battery is, that whereas in the battery the sole crushing power is weight, that is gravity, in the stamp the weight is only secondary to <he velocity, t ho power being the velocity multiplied by the weight. The stamp is being driven by the Moanatairi battery, freely left at the disposal of the agent (Mr C. E. Cooke, A.M. I.C. E , Auckland). The manager of tiie battery, Mr Wolff, and assistants of the b.itte.y lent vdu ibl<» ai I, whilst My T. A. Dunlop supervised its erection. Further trials took place on Saturday, and they cinnot be considered otherwise than satisfactory, A great number of persons interested in crushing machinery, and many of them well acquainted therewith, inspected this novel crusher, which has attracted much attention in the district, and the verdict of an overwhelming majority is in its favour. Some, of course, think they can see wherein it could be modified to advantage, or improve!, but the almost unanimous opinion pronounces the priucip'e demonstrated. Quartz from the Moana»airi No. 1 reef was crushed, probably finer than ever quartz was crushed be- j fore, with the buttery running at the speed of about 210 blows a minute. TlK 1 gratings — perhaps wire gauze would be a more accurate term, for it is woven wire and not punctured plate — were estimated at 2500 holes to the square inch. The motive power was certainly not more than five horse-power, probably about four horse-power. This battery should crush ten tons of quartz in the twenty-fuur hours comfortably, with a solid foundation, and plentiful supply of water to keep the gratings clear, and perhaps 12 or 15 tons. It is calculated that the ordinary type of buttery requires one horse-power per stamper. A very general opinion prevails that many lodes on the Karaka, Tararu, and other creeks, also the Karangahake district and elsewhere, which hitherto have not been worked to pay could with tliis battery be renlercd profitable.. A-5 some May conclude that the quaitz in the stamper box would soon de^tioy the grating, it may be mentioned that, it is protected by a guard or eoaivr grating, througu which the particles h.-u-p fir^t to pass. As the stuff in the box is perpetually in motion, it cannot settle between the two gratings, but any which escapes through the first, but will not p.iss through the second or finer set, is forced back to be reduced finer. — Own Correspondent, Herald.