59 
battery of thirty revolving stampers, five heads in each box. The whole of the 
machinery, including the water and tailings pumps, is driven by a horizontal steam 
engine, having a cylinder 22 in. diameter, with a stroke of 4 ft. 6 in. The engine is 
fitted up with variable expansion gear, and Tangve’s patent governor. A double- 
acting horizontal air-pump is used, the piston rod being coupled direct on to the outer 
end of piston rod of the steam engine. The engine is calculated for, and erected so, 
that it_ is capable of driving, when required, an additional battery of thirty heads. 
Steam is supplied from two boilers, 28 feet long, having each a diameter of 6 feet, 
constructed with Gallaway’s patent tubes and water bridge in the firing tubes. The 
boilers are fed with water by one of Tangyc’s patent steam pumps, which is a very 
great improvement on the old method of "feeding by a pump attached to the steam 
engine; by using the steam pump, the water in boilers may be maintained at the 
correct level, no matter whether the engine be working: or not. 
1 lie cast-iron frames or horses of the battery are of an improved design, and 
very massive. One great advantage in their construction is that they do not project 
before the fronts of the stamper boxes, thereby leaving a clear working room at the 
boxes and the head of ripple tables. The plummer blocks for the cam shafts are cast 
on the girder portion of the frames, and are fitted with strong brasses, caps, and bolts. 
On the girders are also fixed the plummer blocks for counter shafting. 
The guides of stamper shanks are very strong ones, and well secured to the 
frames. The cam shafts are arranged to work ten heads each, driven by spur wheels 
and clutch gearing, so that any ten or the whole thirty (30) heads can be worked as 
desired. The counter shafting at the driving end next to the engine is 7J inches 
diameter, the lengths of shafting being secured together with strong cast-iron turned 
flange couplings. At front of frames or horses are fixed cast-iron brackets for 
carrying the water pipes, and a very substantial footboard or platform ; a strong hand 
railing of wrought-iron gas piping is fixed to the outer edge of the footboard. The 
stamper boxes are of the latest improved design, being fitted with doulde splash doors 
of wrought iron, wood covers and inside splash boards. On tops of covers are 
fixed gun-metal pipes, &c., for conveying feed water into boxes. The stamper boxes 
are provided with false bottoms of the best scrap hammered iron. The shanks are 
3| ; in. diameter, screwed to receive discs 94 in. in diameter. The cams are strong 
wrought iron, Seymour’s patent. The ripple and blanket tables are very substantial 
ones, fitted with cast-iron wells for mercury, the principal timber used in the tables 
being Californian red pine. At the lower ends of blanket tables are fixed Halley’s 
patent percussion table ; after the tailings have left these tables, they are raised by a 
tailings pump, and conducted by shutes to be further treated by cradling, &c. 
The water for supplying the battery and injection for condenser is raised by a 
plunger pump; the water is raised into a large wrought-iron tank placed about 3 feet 
above the centre of the engine. 
Both tailings and water pump are worked by separate bell cranks and sweep 
rod; this allows the pumps to work at any length of stroke found necessary. The 
steam engine is erected upon a substantial bed of brick and stone work, the engine 
platform is elevated so high from the flooring of house that it enables the engineer in 
charge to overlook the whole of the machinery at work. 
The buildings over battery engine and boilers are enclosed and covered in with 
galvanized corrugated iron. The whole of the flooring of main building of battery is 
laid with asphalte. 
PYRITES.—GOLD-SAVING APPLIANCES. 
Treatment of Pyrites .-—“ There is, no doubt,” observes Mr. Cosmo Newbery, 
in his Laboratory Report for 1883, “ a great deal of gold remaining in our tailing 
heaps, but each ounce is divided into very minute grains, and each is locked up in 
very small grains of quartz, distributed through some four or five tons of tailings. I do 
not think that more than 4dwt. or 5dwt. of gold will be found in any quartz tailings 
where modern machinery is in use, and where flic quartz has been free from pyritous 
