When the hour of eleven has struck, he sweeps up the charcoal ashes with
a broom and throws them out of the crucible. Then he climbs on to the
dome, and passing his hand in through its opening, and dipping an old linen
rag in a bucket of water mixed with ashes, he moistens the whole of the
crucible and sweeps it. In this way he uses two bucketsful of the mixture,
each holding five Roman sextaríi,28 and he does this lest the crucible,
when the metals are being parted, should break open; after this he rubs the
crucible with a doe skin, and fills in the cracks. Then he places at the left side
of the channel, two fragments of hearth-lead, laid one on the top of the other,
so that when partly melted they remain fixed and form an obstacle, that the
litharge will not be blown about by the wind from the bellows, but remain in
its place. It is expedient, however, to use a brick in the place of the hearth
lead, for as this gets much hotter, therefore it causes the litharge to form
more rapidly. The crucible in its middle part is made two palms and as
many digits deeper.29
a broom and throws them out of the crucible. Then he climbs on to the
dome, and passing his hand in through its opening, and dipping an old linen
rag in a bucket of water mixed with ashes, he moistens the whole of the
crucible and sweeps it. In this way he uses two bucketsful of the mixture,
each holding five Roman sextaríi,28 and he does this lest the crucible,
when the metals are being parted, should break open; after this he rubs the
crucible with a doe skin, and fills in the cracks. Then he places at the left side
of the channel, two fragments of hearth-lead, laid one on the top of the other,
so that when partly melted they remain fixed and form an obstacle, that the
litharge will not be blown about by the wind from the bellows, but remain in
its place. It is expedient, however, to use a brick in the place of the hearth
lead, for as this gets much hotter, therefore it causes the litharge to form
more rapidly. The crucible in its middle part is made two palms and as
many digits deeper.29
There are some who having thus prepared the crucible, smear it over
with incense30, ground to powder and dissolved in white of egg, soaking
it up in a sponge and then squeezing it out again; there are others who
smear over it a liquid consisting of white of egg and double the amount of
bullock's blood or marrow. Some throw lime into the crucible through a
sieve.
with incense30, ground to powder and dissolved in white of egg, soaking
it up in a sponge and then squeezing it out again; there are others who
smear over it a liquid consisting of white of egg and double the amount of
bullock's blood or marrow. Some throw lime into the crucible through a
sieve.
Afterward the master of the works weighs the lead with which the gold
or silver or both are mixed, and he sometimes puts a hundred centumpondía31
into the crucible, but frequently only sixty, or fifty, or much less. After it
has been weighed, he strews about in the crucible three small bundles of
straw, lest the lead by its weight should break the surface. Then he places
in the channel several cakes of lead alloy, and through the aperture at the rear
of the dome he places some along the sides; then, ascending to the opening at
the top of the dome, he arranges in the crucible round about the dome the
cakes which his assistant hands to him, and after ascending again and passing
his hands through the same aperture, he likewise places other cakes inside the
crucible. On the second day those which remain he, with an iron fork,
places on the wood through the rear aperture of the dome.
or silver or both are mixed, and he sometimes puts a hundred centumpondía31
into the crucible, but frequently only sixty, or fifty, or much less. After it
has been weighed, he strews about in the crucible three small bundles of
straw, lest the lead by its weight should break the surface. Then he places
in the channel several cakes of lead alloy, and through the aperture at the rear
of the dome he places some along the sides; then, ascending to the opening at
the top of the dome, he arranges in the crucible round about the dome the
cakes which his assistant hands to him, and after ascending again and passing
his hands through the same aperture, he likewise places other cakes inside the
crucible. On the second day those which remain he, with an iron fork,
places on the wood through the rear aperture of the dome.
When the cakes have been thus arranged through the hole at the top of
the dome, he throws in charcoal with a basket woven of wooden twigs. Then
he places the lid over the dome, and the assistant covers over the joints with
lute. The master himself throws half a basketful of charcoal into the crucible
through the aperture next to the nozzle pipe, and prepares the bellows, in
order to be able to begin the second operation on the morning of the following
day. It takes the space of one hour to carry out such a piece of work, and
the dome, he throws in charcoal with a basket woven of wooden twigs. Then
he places the lid over the dome, and the assistant covers over the joints with
lute. The master himself throws half a basketful of charcoal into the crucible
through the aperture next to the nozzle pipe, and prepares the bellows, in
order to be able to begin the second operation on the morning of the following
day. It takes the space of one hour to carry out such a piece of work, and