DRESSING OF ORES 



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small and a large circular table, each rotated by means of a tangent wheel and screw. 

 Slime of the fourth class, exceedingly fine, passes first to the small table 10 feet 

 diameter, and after being deprived of the greater portion of its ore, flows to the larger 



a. . 



table 18 feet diameter, where it is divided into a weakly-enriched product and waste. 

 The fall of the table is 5, and one revolution is performed in four minutes : the 



washing water is distributed by means of 3 short wrought-iron pipes, through a line of 

 perforated holes, and a segmental launder ; sufficient water being supplied to effect the 

 desired separation, the brushes making 100 strokes per minute serving tQ clean the 



