DRESSING OF ORES 



103 



battery box is set on a foundation of timber shown in jig. 678 ; the length of timbers in 

 the under framing being 10 feet, depth 15 inches. On these transverse timbers are set 

 running timbers 6 feet 6 inches wide, surmounted by logs having an aggregate width 

 of 36 inches. On the latter rests the battery box. This is constructed partly of wood 



678 



and partly of iron, with an internal iron casing, a lifter, b feeding shoot, d launder 

 for supplying water, e, e back and front grate ways 9 inches wide, / stamp head, q 

 cast-iron bed 3 inches thick and 10 inches wide )t ; perforated plate, Jc mercury boxes. 

 The sectional width of head is 9 inches, depth 20 inches ; width of internal casing 

 15 inches, width of battery box 18 inches, depth from feeding shoot to bottom of foot 

 plate 4 feet 6 inches, depth from bottom edge of grate to surface of stamper plate 4 

 inches. The weight of each head and lifter is 800 cwts. ; number of blows, made 

 per head per minute, 75 ; quartz reduced per head per 24 hours, and passed through 

 screens having ten holes per lineal inch, 4 tons ; quantity of water required per head 

 per minute 8 gallons or 2880 per ton of quartz. The following statistical matter, com- 

 piled from E. Brough Smyth's most able and exhaustive work on the ' G old-Fields and 

 Mineral Districts of Victoria,' will indicate a variety of details connected with stamp- 

 ing machinery in that wealthy and thriving colony : 



