1of
de-silverized lead, or of litharge, as will make it possible to obtain from
that
alloy a liquation cake containing two and a quarter centumpondía of lead,
in which manner in four of these cakes there will be three centumpondía of
copper and nine centumpondía of lead. The lead which liquates from these
cakes weighs seven centumpondia, in each centumpondíum of which there is
a quarter of a líbra of silver and a little more than a sícílícus. About seven
uncíae of silver remain in the exhausted liquation cakes and in the liquation
thorns, if we may be allowed to make common the old name (spínae=thorns)
and bestow it upon a new substance. If in three-quarters of a centumpondíum
of copper there is less than three-quarters of a líbra of silver, or three-quarters
and a semí-uncía, then as much rich lead must be added as will produce one
of the proportions of silver in the copper-lead alloy above mentioned; this
is the “third” alloy. To this is added such an amount of de-silverized lead
or of litharge, that a liquation cake made from it contains in all two and
three-quarters centumpondía of lead. In this manner four such cakes will
contain three centumpondía of copper and eleven centumpondía of lead.
The lead which these cakes liquate, when they are melted in the furnace,
weighs about nine centumpondía, in each centumpondíum of which there is
a quarter of a líbra and more than a sícílícus of silver; and seven uncíae of
silver remain in the exhausted liquation cakes and in the liquation thorns.
If, however, in three-quarters of a centumpondíum of copper there is less than
ten-twelfths of a líbra or ten-twelfths of a libra and a semí-uncía of silver,
then such a proportion of rich lead is added as will produce in the copper-lead
alloy one of the proportions of silver which I mentioned above; this is the
“fourth” alloy. To this is added such a weight of de-silverized lead or of
litharge, that a liquation cake made from it contains three centumpondía of
alloy a liquation cake containing two and a quarter centumpondía of lead,
in which manner in four of these cakes there will be three centumpondía of
copper and nine centumpondía of lead. The lead which liquates from these
cakes weighs seven centumpondia, in each centumpondíum of which there is
a quarter of a líbra of silver and a little more than a sícílícus. About seven
uncíae of silver remain in the exhausted liquation cakes and in the liquation
thorns, if we may be allowed to make common the old name (spínae=thorns)
and bestow it upon a new substance. If in three-quarters of a centumpondíum
of copper there is less than three-quarters of a líbra of silver, or three-quarters
and a semí-uncía, then as much rich lead must be added as will produce one
of the proportions of silver in the copper-lead alloy above mentioned; this
is the “third” alloy. To this is added such an amount of de-silverized lead
or of litharge, that a liquation cake made from it contains in all two and
three-quarters centumpondía of lead. In this manner four such cakes will
contain three centumpondía of copper and eleven centumpondía of lead.
The lead which these cakes liquate, when they are melted in the furnace,
weighs about nine centumpondía, in each centumpondíum of which there is
a quarter of a líbra and more than a sícílícus of silver; and seven uncíae of
silver remain in the exhausted liquation cakes and in the liquation thorns.
If, however, in three-quarters of a centumpondíum of copper there is less than
ten-twelfths of a líbra or ten-twelfths of a libra and a semí-uncía of silver,
then such a proportion of rich lead is added as will produce in the copper-lead
alloy one of the proportions of silver which I mentioned above; this is the
“fourth” alloy. To this is added such a weight of de-silverized lead or of
litharge, that a liquation cake made from it contains three centumpondía of