1sized
tin-stone which melts quickly, but less of the large ones which melt
slowly, and a moderate quantity of the medium-sized which holds the middle
course. Those who do not smelt the tin-stone in furnaces made sometimes
wide, sometimes medium, or sometimes narrow, in order that great loss
should not be occasioned, throw in first the smallest size, then the medium,
then the large size, and finally those which are not quite pure; and the blast
of the bellows is altered as required. In order that the tin-stone thrown
into the furnace should not roll off from the large charcoal into the forehearth
before the tin is melted out of it, the smelter uses small charcoal; first some
of this moistened with water is placed in the furnace, and then he frequently
repeats this succession of charcoal and tin-stone.
slowly, and a moderate quantity of the medium-sized which holds the middle
course. Those who do not smelt the tin-stone in furnaces made sometimes
wide, sometimes medium, or sometimes narrow, in order that great loss
should not be occasioned, throw in first the smallest size, then the medium,
then the large size, and finally those which are not quite pure; and the blast
of the bellows is altered as required. In order that the tin-stone thrown
into the furnace should not roll off from the large charcoal into the forehearth
before the tin is melted out of it, the smelter uses small charcoal; first some
of this moistened with water is placed in the furnace, and then he frequently
repeats this succession of charcoal and tin-stone.
The tin-stone, collected from material which during the summer was
washed in a ditch through which a stream was diverted, and during the winter
was screened on a perforated iron plate, is smelted in a furnace a palm wider
than that in which the fine tin-stone dug out of the earth is smelted. For
the smelting of these, a more vigorous blast of the bellows and a fiercer fire
is needed than for the smelting of the large tin-stone. Whichever kind of
tin-stone is being smelted, if the tin first flows from the furnace, much of it is
made, and if slags first flow from the furnace, then only a little. It happens
that the tin-stone is mixed with the slags when it is either less pure or
ferruginous—that is, not enough roasted—and is imperfect when put into
the furnace, or when it has been put in in a larger quantity than was neces
sary; then, although it may be pure and melt easily, the ore either runs
out of the furnace at the same time, mixed with the slags, or else it settles
so firmly at the bottom of the furnace that the operation of smelting being
necessarily interrupted, the furnace freezes up.
washed in a ditch through which a stream was diverted, and during the winter
was screened on a perforated iron plate, is smelted in a furnace a palm wider
than that in which the fine tin-stone dug out of the earth is smelted. For
the smelting of these, a more vigorous blast of the bellows and a fiercer fire
is needed than for the smelting of the large tin-stone. Whichever kind of
tin-stone is being smelted, if the tin first flows from the furnace, much of it is
made, and if slags first flow from the furnace, then only a little. It happens
that the tin-stone is mixed with the slags when it is either less pure or
ferruginous—that is, not enough roasted—and is imperfect when put into
the furnace, or when it has been put in in a larger quantity than was neces
sary; then, although it may be pure and melt easily, the ore either runs
out of the furnace at the same time, mixed with the slags, or else it settles
so firmly at the bottom of the furnace that the operation of smelting being
necessarily interrupted, the furnace freezes up.
The tap-hole of the forehearth is opened and the tin is diverted into the
dipping-pot, and as often as the slags flow down the sloping floor of the build
ing they are skimmed off with a rabble; as soon as the tin has run out of
the forehearth, the tap-hole is again closed up with lute mixed with powdered
charcoal. Glowing coals are put in the dipping-pot so that the tin, after it
has run out, should not get chilled. If the metal is so impure that nothing
can be made from it, the material which has run out is made into cakes to be
re-smelted in the hearth, of which I shall have something to say later; if the
metal is pure, it is poured immediately upon thick copper plates, at first in
straight lines and then transversely over these to make a lattice. Each of
these lattice bars is impressed with an iron die; if the tin was melted out
of ore excavated from mines, then one stamp only, namely, that of the
Magistrate, is usually imprinted, but if it is made from tin-stone collected on
the ground after washing, then it is impressed with two seals, one the
Magistrate's and the other a fork which the washers use. Generally, three
of this kind of lattice bars are beaten and amalgamated into one mass with a
wooden mallet.
dipping-pot, and as often as the slags flow down the sloping floor of the build
ing they are skimmed off with a rabble; as soon as the tin has run out of
the forehearth, the tap-hole is again closed up with lute mixed with powdered
charcoal. Glowing coals are put in the dipping-pot so that the tin, after it
has run out, should not get chilled. If the metal is so impure that nothing
can be made from it, the material which has run out is made into cakes to be
re-smelted in the hearth, of which I shall have something to say later; if the
metal is pure, it is poured immediately upon thick copper plates, at first in
straight lines and then transversely over these to make a lattice. Each of
these lattice bars is impressed with an iron die; if the tin was melted out
of ore excavated from mines, then one stamp only, namely, that of the
Magistrate, is usually imprinted, but if it is made from tin-stone collected on
the ground after washing, then it is impressed with two seals, one the
Magistrate's and the other a fork which the washers use. Generally, three
of this kind of lattice bars are beaten and amalgamated into one mass with a
wooden mallet.
The slags that are skimmed off are afterward thrown with an iron shovel
into a small trough hollowed from a tree, and are cleansed from charcoal
into a small trough hollowed from a tree, and are cleansed from charcoal
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