1When the
masses of lead are to be melted, the workman first places the wood
in the hearth so that one end of each billet faces the wall, and the other end
the dipping-pot. Then, assisted by other workmen, he pushes the mass
of lead forward with crowbars on to a low trolley, and draws it to the
crane. The trolley consists of planks fastened together, is two and one-half
feet wide and five feet long, and has two small iron axles, around which at
each end revolve small iron wheels, two palms in diameter and as many digits
wide. The trolley has a tongue, and attached to this is a rope, by which it is
drawn to the crane. The crane is exactly similar to those in the second part
of the works, except that the crane-arm is not so long. The tongs in whose
jaws6 the masses of lead are seized, are two feet a palm and two digits long;
both of the jaws, when struck with a hammer, impinge upon the mass and are
driven into it. The upper part of both handles of the tongs are curved back,
the one to the right, the other to the left, and each handle is engaged in one
of the lowest links of two short chains, which are three links long. The upper
links are engaged in a large round ring, in which is fixed the hook of a chain
let down from the pulley of the crane-arm. When the crank of the crane
is turned, the mass is lifted and is carried by the crane-arm to the hearth and
placed on the wood. The workmen wheel up one mass after another and
place them in a similar manner on the wood of the hearth; masses which
weigh a total of about a hundred and sixty centumpondía7 are usually placed
upon the wood and melted at one time. Then a workman throws charcoal
on the masses, and all are made ready in the evening. If he fears that it may
rain, he covers it up with a cover, which may be moved here and there; at the
back this cover has two legs, so that the rain which it collects may flow down
the slope on to the open ground. Early in the morning of the following day,
he throws live coals on the charcoal with a shovel, and by this method the
masses of lead melt, and from time to time charcoal is added. The lead, as
soon as it begins to run into the dipping-pot, is ladled out with an iron ladle
into copper moulds such as the refiners generally use. If it does not cool
immediately he pours water over it, and then sticks the pointed pick into
it and pulls it out. The pointed end of the pick is three palms long and
the round end is two digits long. It is necessary to smear the moulds with a
wash of lute, in order that, when they have been turned upside down and
struck with the broad round end of the pick, the cakes of lead may fall out
easily. If the moulds are not washed over with the lute, there is a risk that
they may be melted by the lead and let it through. Others take hold of a
billet of wood with their left hand, and with the heavy lower end of it they
pound the mould, and with the right hand they stick the point of the pick
into the cake of lead, and thus pull it out. Then immediately the workman
pours other lead into the empty moulds, and this he does until the work of
melting the lead is finished. When the lead is melted, something similar to
litharge is produced; but it is no wonder that it should be possible to make
in the hearth so that one end of each billet faces the wall, and the other end
the dipping-pot. Then, assisted by other workmen, he pushes the mass
of lead forward with crowbars on to a low trolley, and draws it to the
crane. The trolley consists of planks fastened together, is two and one-half
feet wide and five feet long, and has two small iron axles, around which at
each end revolve small iron wheels, two palms in diameter and as many digits
wide. The trolley has a tongue, and attached to this is a rope, by which it is
drawn to the crane. The crane is exactly similar to those in the second part
of the works, except that the crane-arm is not so long. The tongs in whose
jaws6 the masses of lead are seized, are two feet a palm and two digits long;
both of the jaws, when struck with a hammer, impinge upon the mass and are
driven into it. The upper part of both handles of the tongs are curved back,
the one to the right, the other to the left, and each handle is engaged in one
of the lowest links of two short chains, which are three links long. The upper
links are engaged in a large round ring, in which is fixed the hook of a chain
let down from the pulley of the crane-arm. When the crank of the crane
is turned, the mass is lifted and is carried by the crane-arm to the hearth and
placed on the wood. The workmen wheel up one mass after another and
place them in a similar manner on the wood of the hearth; masses which
weigh a total of about a hundred and sixty centumpondía7 are usually placed
upon the wood and melted at one time. Then a workman throws charcoal
on the masses, and all are made ready in the evening. If he fears that it may
rain, he covers it up with a cover, which may be moved here and there; at the
back this cover has two legs, so that the rain which it collects may flow down
the slope on to the open ground. Early in the morning of the following day,
he throws live coals on the charcoal with a shovel, and by this method the
masses of lead melt, and from time to time charcoal is added. The lead, as
soon as it begins to run into the dipping-pot, is ladled out with an iron ladle
into copper moulds such as the refiners generally use. If it does not cool
immediately he pours water over it, and then sticks the pointed pick into
it and pulls it out. The pointed end of the pick is three palms long and
the round end is two digits long. It is necessary to smear the moulds with a
wash of lute, in order that, when they have been turned upside down and
struck with the broad round end of the pick, the cakes of lead may fall out
easily. If the moulds are not washed over with the lute, there is a risk that
they may be melted by the lead and let it through. Others take hold of a
billet of wood with their left hand, and with the heavy lower end of it they
pound the mould, and with the right hand they stick the point of the pick
into the cake of lead, and thus pull it out. Then immediately the workman
pours other lead into the empty moulds, and this he does until the work of
melting the lead is finished. When the lead is melted, something similar to
litharge is produced; but it is no wonder that it should be possible to make
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