Lead 
207 
down the gutter for a short time, and then prevents any 
more escaping, by lightly raising up the brouse against the 
glitter with the corner of his shovel. 
Two men will smelt about six bings of good ore a day ? 
and from these produce 24 pigs of lead, weighing 1541bs„ 
each. 
It is advisable to draw the hearth at the end of every 
twelve hours, in order that it may cool ; for a cool hearth 
works pleasanter, and makes better produce than one which 
has been suffered to heat. The hearth should be drawn 
about two watchings after throwing on the last of the six 
bings of ore. As soon as the hearth is watched-out the 
last time, the action of the bellows is stopped, and the 
smelters draw out the whole of the hot brouse with their 
shovels, and throw it on the floor to cool, picking out such 
slags as they may observe ; they also remove whatever 
adheres to the sides or back. 
If the hearth has been properly attended, and a due pro- 
portion of fuel used, it will scarcely appear hotter in one 
part than another ; and, if it has been working with a free 
ore, should not appear hotter than a very dull obscure red 
heat. 
With a free ore, the hearth, when fresh set-up, works 
as before described, the blast finding its way equally 
through all parts of the breast. The brouse, when watch- 
ed-out, is dry, and mostly in small pieces, the slags fin^ 
and easily distinguished by their cavernous appearance 
and brighter colour, and the lead flows from the hearth 
scarcely red hot. Lead ore, which contains muc|i silver 
or copper, or which has not been properly cleared from 
the gangue with which it is mixed in the vein, requires 
particular attention on the part of the smelter : instead of 
working dry and open, it becomes soft and pasty; the 
slag, instead of separating in firm pieces, is diffused 
through the whole like a half- melted scoria, and the least 
