DRESSING OP ORES 



139 



portion of waste along with a littlo light ore is washed into the receptacles underneath, 

 1'rcm whence it may flow into strips or buddies for further separation, or is other- 

 wise manipulated upon a second buddle. The water is supplied to the machine 

 under pressure by the pipe L. This apparatus will wash from 80 to 100 cubic feet 

 of free slimes in 10 hours, or from 60 to 80 cubic feet of tough slimes in the same 

 period. Lead stuff affording 4 per cent, with a light waste has been enriched to 

 40 per cent, in a second revolution, and in a third and fourth rotation 40 per cent, 

 slime has been enriched so as to yield 60 per cent, of ore. The buddle table 

 makes two revolutions per minute; its diameter varies from 8 to 10 feet, and the 

 power required is about one-tenth of a horse-power. One boy can servo four 

 buddies. 



Rittingers Rotating Buddie. This apparatus is employed at Schemnitz, and is 

 applicable to the treatment of fine slimes containing but a small proportion of 

 metallic substances. The accompanying sketch (fig. 734) will serve to explain 

 its construction and action. The machine may be said to consist of four principal 

 parts : 



1st. The vertical axle a, which carries the buddle. 



2nd. The surface of the buddle b. 



3rd. The concentric launders c c', for supplying the diluted slimes, as well as clean 

 water to wash the mineral. 



4th. The concentric launders d d, beneath the buddle for receiving the concentrated 

 minerals and waste. 



The vertical axle a, is fitted with a cast-iron centre-piece, which receives 16 wooden 

 arms; these support the same number of segments, and form a circle 16 feet in 

 diameter. Each segment is divided into two parts, by radial strips of wood, so that 

 the whole surface of the buddle is divided into thirty-two parts, each being 5^ feet 

 long, and having a fall of about 6 inches towards the centre. 



Motion is given by a tangent wheel and screw geared at the upper end of the axle, 

 one revolution in ten minutes being the required speed. Above the buddle are two 

 concentric launders, the one </, at the periphery, 

 being for clean water, the other c, nearest the 

 centre, for the contents of the sizing apparatus. 

 The stuff is introduced by means of feeding 

 boards on the outer circumference of the buddle. 



Between each feeding board a fine sheet of 

 water flows to the buddle from the launder c. 



After the last feeding board, the launder 

 forms a curve towards the centre of the buddle, 

 and supplies along its length a thin fine stream 

 of water, which washes the deposited stuff from 

 top to bottom, carrying away all the lighter 

 particles, and leaving only the heaviest minerals 

 on the surface of the buddle. The buddle, after 

 passing this point in the course of its rotation, 

 comes under a strong jet of water flowing from 

 a pipe/, supplied from a cistern about 12 feet 

 above. This water flows with sufficient force 

 to drive the concentrated mineral into the 

 launders d d, which is divided into different com- 

 partments, for receiving the middles and waste 

 from the buddle during its revolution. These 

 are thrown away, unless it be found that the 

 middles are worth repassing over the buddle. 

 The finer the slimes, the more perfect is the result. The slimes from the sizing 

 apparatus should be thin, from 2;j to 4j Ibs. of sand to a cubic foot of water being 

 sufficient. 



The water required for cleansing is from eight to nine-tenths of a cubic foot per 

 minute. 



The water for driving off the clean product is from one and a half to one and six- 

 tenths of a cubic foot per minute. 



Altogether, the quantity of water required per minute is about 2 cubic feet. 



The buddle, if properly constructed, extracts about 80 per cent, of the ore contained 

 in the slimes, and will treat about 1 cwt. per hour. One-twentieth of a horse-power is 

 sufficient for rotating the buddle. 



A valuable set of buddies for enriching palpable slimes, has been in use for many 

 years at the lead and silver ore dressing establishment near Ems, Prussia. 



The apparatus is shown in elevation fig. 735 and plan fig. 736, and consists of a 



