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The save-all and shower-box will be sufficient to take the tail-waters from two pans by a very slight increase of the diameter of save-all and by lengthening of the shower-box. In the inventors' experiments they have found that all the fine flour-gold is lost through its extreme fineness and the want of suitable appliances to insure amalgamation. Assays made by Mr. Rew for a number of years showed that gold is lost in dirty water at the rate of lgr. for each 300 gallons of water used in treating our ores, and in many instances from ldwt. to Bdwt. per ton of ore. The lower scale of averages—namely, lgr. per 300 gallons of water —will, by taking the quantity of tons in both quartz and alluvial mining, as shown by the Mining Registrars' reports, show that over six hundred thousand pounds' worth of gold is lost annually. A company has been formed, under the title of the Stahl-Rew Amalgamating-pan Company, to patent the process through all the colonies, America, and Europe. Reference to Plan, Fig. 1. A, Inside of pan, to contain slimes after being ground and amalgamated, passing away by the overflow shoot at A l , a, Inner circle, of sheet iron, a l , Outer circle, of either cast- or sheet-iron, of pan. The epace of 4in. between the two circles of iron marked a 2 is used for introducing the feed direct under the muller-shoes and mercury-well. 44 3 , Distributing-box, sft. long. A 3 , Pine mercurywell, with pine check-board. B, Outer feed shoot. 81,B l , Inner feed shoot. C, Main cast-iron bottom, in four segments, c, False bottoms (twelve pieces). D, Muller. d, Rubber fin. square. a\, iron liner. 3in. deep by fin. thick; on the face of this liner the rubber presses to make water-tight joint, thereby insuring the feed passing under and between the grinding-surface, passing into body of pan through the centre hole. E, Three-inch vertical driving-shaft, c, Driving or muller-arms. e l , Head of driver. F, Sleeve or column, containing brasses at top for vertical shaft. /, Counter sunk bolts by which centre column of sleeve is bolted down to main bottom. G, Amalgamated copper or electro-silvered copper-plate wings, g, Angle-iron ribs for fastening wings to. H, Amalgamated copper plate, floating on bed of mercury, to receive shower of tail-waste of pan. h, Mercury, h l , Mercury-well. I, Vessel for generating hydrogen gas from muriatic acid, zinc, and ammonia-chloride, for keeping mercury bright, giving it the power to dispel the air-film surrounding particles of gold, thereby insuring perfect amalgamation, i, Pipe for conveying hydrogen gas to mercury. i\, Regu-lating-tap. J, Valves to allow of alternate feed, centre or outside. J l , Perforated shower-plate, drop 14in. X l , Save-all complete, intended to revolve slowly over a bed of mercury, whereby all floured mercury or fine amalgam may be collected if any escape the floating plate, and collect any mercury that by accident or otherwise may pass through other receptacles. X, Revolving disc or muller, carrying on the under-side 24 amalgamated copper-lined pine battens, with spaces of fin. in between each batten. This disc is for rubbing the tail-waste into the mercury below. A corrugated copper disc can be used if preferred, k, Bed of mercury. k t , Head of driver and central-feed hopper, the feed falling from shoot on to perforated iron plate, for equal distribution on to mercury. L, Collecting-tub for cleaning up and collecting mercury and amalgam. I, Discharge-pipes into various mercury-wells to central cleaning-up pan.— Victorian Mining Beport.

White's Amalgamating Pan. This pan revolves at the angle shown at thirty-five revolutions per minute. Each charge contains about l-|cwt, of tailings, with sufficient water added to bring the charge within about 3in. from the lip at low edge of pan. This is allowed to amalgamate with about 251b. silver for one hour, and then discharged over Halley's percussion-table with an ordinary lin. syphon-pipe. The quicksilver remains in the pan, and another charge added. This is continued generally for a few days before cleaning out, but varies according to the quality of the sand treated. To prevent the pan from wearing, the bottom and sides are covered with a layer of coarse gravel, sand, and cement, the bottom about 2in. thick. When this thoroughly sets and hardens, it not only effectually prevents any wear of the pan, but assists in amalgamating, being rougher on the surface than the castiron. Each coating of cement lasts about twelve months with ordinary work. The number of revolutions, quantity of stuff per charge, and time of treatment vary to a certain extent with the nature of the sand treated. These pans are in use in the Wimmera Crushing Company's works, Stawell, and are found to be preferable in every way to the amalgamating-barrel. Mr. E. R. Meekison, Inspector of Mining Machinery in Victoria, reports as follows on this invention : " This pan, in my opinion, is much superior to barrels for amalgamating, and does away with the barrel filling and making tight joints, also collecting quicksilver, and, in consequence, a greater quantity of sand can be treated with less labour and loss of quicksilver than by the use of barrels," — Victorian Mining Beport.

The Pollok Gold-extracting Process. [Industries, 14th February, 1890.] The Pollok process is, like the great majority of gold-extracting processes which have been hitherto patented, a chlorination one—i.e., the reagent used for the purpose of dissolving out the