1described above, is drawn backward and forward
upon narrow boards of
equal length placed over a long box; the powder which falls through the
sieve into the box is suitable for the mixture; the lumps that remain in the
sieve are thrown away by some people, but by others they are placed under
the stamps. This powdered earth is mixed with powdered charcoal, moist
ened, and thrown into a pit, and in order that it may remain good for a long
time, the pit is covered up with boards so that the mixture may not
become contaminated.
equal length placed over a long box; the powder which falls through the
sieve into the box is suitable for the mixture; the lumps that remain in the
sieve are thrown away by some people, but by others they are placed under
the stamps. This powdered earth is mixed with powdered charcoal, moist
ened, and thrown into a pit, and in order that it may remain good for a long
time, the pit is covered up with boards so that the mixture may not
become contaminated.
They take two parts of pulverised charcoal and one part of powdered
earth, and mix them well together with a rake; the mixture is moistened by
pouring water over it so that it may easily be made into shapes resembling
snowballs; if the powder be light it is moistened with more water, if heavy
with less. The interior of the new furnace is lined with lute, so that the
cracks in the walls, if there are any, may be filled up, but especially in order
to preserve the rock from injury by fire. In old furnaces in which ore has
been melted, as soon as the rocks have cooled the assistant chips away, with
a spatula, the accretions which adhere to the walls, and then breaks them
up with an iron hoe or a rake with five teeth. The cracks of the furnace are
first filled in with fragments of rock or brick, which he does by passing his
hand into the furnace through its mouth, or else, having placed a ladder against
it, he mounts by the rungs to the upper open part of the furnace. To the
upper part of the ladder a board is fastened that he may lean and recline
against it. Then standing on the same ladder, with a wooden spatula, he
smears the furnace walls over with lute; this spatula is four feet long, a digit
thick, and for a foot upward from the bottom it is a palm wide, or even
wider, generally two and a half digits. He spreads the lute equally over the
inner walls of the furnace. The mouth of the copper pipe9 should not pro
trude from the lute, lest sows10 form round about it and thus impede the
melting, for the furnace bellows could not force a blast through them. Then
the same assistant throws a little powdered charcoal into the pit of the fore
hearth and sprinkles it with pulverised earth. Afterward, with a bucket
he pours water into it and sweeps this all over the forehearth pit, and with the
broom drives the turbid water into the furnace hearth and likewise sweeps
it out. Next he throws the mixed and moistened powder into the furnace,
and then a second time mounting the steps of the ladder, he introduces the
rammer into the furnace and pounds the powder so that the hearth is made
solid. The rammer is rounded and three palms long; at the bottom it is five
digits in diameter, at the top three and a half, therefore it is made in the form
of a truncated cone; the handle of the rammer is round and five feet long and
earth, and mix them well together with a rake; the mixture is moistened by
pouring water over it so that it may easily be made into shapes resembling
snowballs; if the powder be light it is moistened with more water, if heavy
with less. The interior of the new furnace is lined with lute, so that the
cracks in the walls, if there are any, may be filled up, but especially in order
to preserve the rock from injury by fire. In old furnaces in which ore has
been melted, as soon as the rocks have cooled the assistant chips away, with
a spatula, the accretions which adhere to the walls, and then breaks them
up with an iron hoe or a rake with five teeth. The cracks of the furnace are
first filled in with fragments of rock or brick, which he does by passing his
hand into the furnace through its mouth, or else, having placed a ladder against
it, he mounts by the rungs to the upper open part of the furnace. To the
upper part of the ladder a board is fastened that he may lean and recline
against it. Then standing on the same ladder, with a wooden spatula, he
smears the furnace walls over with lute; this spatula is four feet long, a digit
thick, and for a foot upward from the bottom it is a palm wide, or even
wider, generally two and a half digits. He spreads the lute equally over the
inner walls of the furnace. The mouth of the copper pipe9 should not pro
trude from the lute, lest sows10 form round about it and thus impede the
melting, for the furnace bellows could not force a blast through them. Then
the same assistant throws a little powdered charcoal into the pit of the fore
hearth and sprinkles it with pulverised earth. Afterward, with a bucket
he pours water into it and sweeps this all over the forehearth pit, and with the
broom drives the turbid water into the furnace hearth and likewise sweeps
it out. Next he throws the mixed and moistened powder into the furnace,
and then a second time mounting the steps of the ladder, he introduces the
rammer into the furnace and pounds the powder so that the hearth is made
solid. The rammer is rounded and three palms long; at the bottom it is five
digits in diameter, at the top three and a half, therefore it is made in the form
of a truncated cone; the handle of the rammer is round and five feet long and
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