Note 15 — BOOK XI.

[Pg 510][15] In this enrichment of copper by the "settling" of the silver in the molten mass the original copper ran, in the two cases given, 60 ozs. 15 dwts. and 85 ozs. 1 dwt. per ton. The whole charge weighed 2,685 lbs., and contained in the second case 114 ozs. Troy, omitting fractions. On melting, 1,060 lbs. were drawn off as "tops," containing 24 ozs. of silver, or running 45 ozs. per ton, and there remained 1,625 lbs. of "bottoms," containing 90 ozs. of silver, or averaging 110 ozs. per ton. It will be noticed later on in the description of making liquation cakes from these copper bottoms, that the author alters the value from one-third librae, a semi-uncia and a drachma per centumpondium to one-third of a libra, i.e., from 110 ozs. to 97 ozs. 4 dwts. per ton. In the Glossary this furnace is described as a spleisofen, i.e., a refining hearth.