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is in the copper is mixed with the remainder of silver ; the copper itself,
equally with the lead, will be changed partly into litharge and partly into
hearth-lead.19 The silver-lead alloy which does not melt is taken from the
margin of the crucible with a hooked bar.
The work of " drying " is distributed into four operations, which are
performed in four days. On the first—as likewise on the other three days—the
master begins at the fourth hour of the morning, and with his assistant chips
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off the stalactites from the exhausted Hquation cakes. They then carry the
cakes to the furnace, and put the stalactites upon the heap of liquation
thorns. The head of the chipping hammer is three palms and as many digits
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leThe first instance given, of 44 centumpondia (3,109 lbs.) lead and one centumpondium
(70.6 lbs.) copper, would indicate that the liquated lead contained 2.2% copper. The second,
of 46 centumpondia (3,250 lbs.) lead and i£ centumpondia copper (106 lbs.), would indicate 3%
copper ; and in the third, 120 centumpondia (8,478 lbs.) lead and six copper (424 lbs.) would show
4.76% copper. This charge of 120 centumpondia in the cupellation furnace would normally
make more than no centumpondia of litharge and 30 of hearth-lead, i.e., saturated furnace
bottoms. The copper would be largely found in the silver-lead " which does not melt," at the
margin of the crucible. These skimmings are afterward referred to as " thorns." It is difficult
to understand what is meant by the expression that the silver which is in the copper is mixed
with the remaining (reliquo) silver. The coppery skimmings from the cupellation furnace are
referred to again in Note 28, p. 539.
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