If the tin is so impure that it cracks when struck with the hammer, it
is not immediately made into lattice-like bars, but into the cakes which I have
spoken of before, and these are refined by melting again on a hearth. This
hearth consists of sandstones, which slope toward the centre and a little
toward a dipping-pot; at their joints they are covered with lute. Dry
logs are arranged on each side, alternately upright and lengthwise, and more
closely in the middle; on this wood are placed five or six cakes of tin which
all together weigh about six centumpondia; the wood having been kindled,
is not immediately made into lattice-like bars, but into the cakes which I have
spoken of before, and these are refined by melting again on a hearth. This
hearth consists of sandstones, which slope toward the centre and a little
toward a dipping-pot; at their joints they are covered with lute. Dry
logs are arranged on each side, alternately upright and lengthwise, and more
closely in the middle; on this wood are placed five or six cakes of tin which
all together weigh about six centumpondia; the wood having been kindled,
A—HEARTHS. B—DIPPING-POTS. C—WOOD. D—CAKES.
E—LADLE. F—COPPER
PLATE. G—LATTICE-SHAPED BARS. H—IRON DIES. I—WOODEN MALLET. K—MASS
OF TIN BARS. L—SHOVEL.
the tin drips down and flows continuously into the dipping-pot which
is on the floor. The impure tin sinks to the bottom of this dipping-pot
and the pure tin floats on the top; then both are ladled out by the master,
who first takes out the pure tin, and by pouring it over thick plates of copper
makes lattice-like bars. Afterward he takes out the impure tin from which
he makes cakes; he discriminates between them, when he ladles and pours,
by the ease or difficulty of the flow. One centumpondium of the lattice-like
bare sells for more than a centumpondium of cakes, for the price of the former
PLATE. G—LATTICE-SHAPED BARS. H—IRON DIES. I—WOODEN MALLET. K—MASS
OF TIN BARS. L—SHOVEL.
the tin drips down and flows continuously into the dipping-pot which
is on the floor. The impure tin sinks to the bottom of this dipping-pot
and the pure tin floats on the top; then both are ladled out by the master,
who first takes out the pure tin, and by pouring it over thick plates of copper
makes lattice-like bars. Afterward he takes out the impure tin from which
he makes cakes; he discriminates between them, when he ladles and pours,
by the ease or difficulty of the flow. One centumpondium of the lattice-like
bare sells for more than a centumpondium of cakes, for the price of the former