Hot Blast in the Smelting of Lead. 173 
Fig. 3 is a crusher of cast iron. Into this the ore and gangue 
is thrown, and reduced so that none of it is larger than half cai 
cubes, and as little of it crushed very fine, as me 
Tig, 
‘ 
Et 
§ Rock erusher used at Rossie.—a, driving pinion, 6, wheel attached to lower 
crusher d, upper crusher, filled with lead and weighed down by lever d. 
Whole ent of the crusher, say 4000 | = 
« Fig. 4 a coe 
% Bis 3) fs 
: f 
La _ - oer sail ee 
- Fig. Aisa tonclaat sieve; A, a square box with iron bottom, Pr 
eee with small holes, stispended in the vat of water, B, in 
