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DRESSING OF ORES 



placed in the prolongation of the shaft of this wheel, -which carries besides a cast-iron 

 toothed wheel, geared with the toothed wheels e e, fixed upon the ends of two of the 

 smooth cylinders. Above the fluted cylinders there is a hopper s, which discharges 

 down between them, by means of a particular mechanism, the ore brought forward by 

 the waggons A. These waggons advance upon a railway, stop above the hopper, and 



empty their contents into it through a trap-hole, which opens outwardly in the middle 

 of their bottom. Below the hopper there is a small bucket called a shoe, into 

 which the ore is shaken down, and which throws it without ceasing upon the 

 cylinders, in consequence of the constant jolts given it by a crank-rod attached to 



