The foreman of the works, according to the different proportions of
silver in each centum-pondium of copper, alloys it with lead, without which
he could not separate the silver from the copper.10 If there be a moderate
10The details of the preparation of liquation cakes—" leading "—were matters of great
concern to the old metallurgists. The size of the cakes, the proportion of silver in the original
copper and in the liquated lead, the proportion of lead and silver left in the residual cakes, all
had to be reached by a series of compromises among militant forces. The cakes were generally
two and one-half to three and one-half inches thick and about two feet in diameter, and
