DRESSING OF ORES 



133 



as middles and tails resulting from the round luddlo, or the tails from strips, &c. A 

 rising column of water is shown at A. This flows into a trough B, and through peg- 

 holes into c. Here the stuff to be treated is introduced, and continually agitated by 

 the boy in attendance. The finer portion passes through the perforated plate at D, 

 and is distributed by the fan-shaped incline E in an uniform sheet on the head of 

 the buddies. A boy stands just below the line of the middles with a wooden 



725 



rake ; with this instrument he continually directs the descending current to the head 

 of the buddle, and by this means succeeds in separating a larger proportion of the 

 ore than would otherwise be done, "Whether the rake or the broom be employed, 

 it is found that some of the fine lead is florrined to the extreme tail of the buddle. In 

 order to prevent this the frame G has been introduced. It is strained with canvas, 



726 



and floats on the water. This canvas retains the fine lead, which is from time to 

 time washed off in a cistern. The section to the first dotted line shows the heads 

 of the buddle ; from this to the second dotted line will be the middles, and from 

 tho second dotted line the tails commence. It must, however, be remarked that the 

 exact line of heads, tails, and middles must depend upon their relative richness. The 



wooden rake is undoubtedly preferable to the broom, as will appear from the following 

 experiment, everything being equal in both trials : 



Stuff operated upon ; tails from washing strips assayed 1 3 per eent. 



No. 1. Heads, assayed 

 2. Middles, 

 3. Tails, 



With broom 

 16 er cent. 



With rake 

 20 per cent. 



