Note note 33, p. 473 — BOOK X.

[33] Stannum, as a term for lead-silver alloys, is a term which Agricola (De Natura Fossilium, pp. 341-3) adopted from his views of Pliny. In the Interpretatio and the Glossary he gives the German equivalent as werk, which would sufficiently identify his meaning were it not obvious from the context. There can be little doubt that Pliny uses the term for lead alloys, but it had come into general use for tin before Agricola's time. The Roman term was plumbum candidum, and as a result of Agricola's insistence on using it and stannum in what he conceived was their original sense, he managed to give considerable confusion to mineralogic literature for a century or two. The passages from Pliny, upon which he bases his use, are (XXXIV, 47): "The metal which flows liquid at the first melting in the furnace is called stannum, the second melting is silver," etc. (XXXIV, 48): "When copper vessels are coated with stannum they produce a less disagreeable flavour, and it prevents verdigris. It is also remarkable that the weight is not increased.... At the present day a counterfeit stannum is made by adding one-third of white copper to tin. It is also made in another way, by mixing together equal parts of tin and lead; this last is called by some argentarium.... There is also a composition called tertiarium, a mixture of two parts of lead and one of tin. Its price is twenty denarii per pound, and it is used for soldering pipes. Persons still more dishonest mix together equal parts of tertiarium and tin, and calling the compound argentarium, when it is melted coat articles with it." Although this last passage probably indicates that stannum was a tin compound, yet it is not inconsistent with the view that the genuine stannum was silver-lead, and that the counterfeits were made as stated by Pliny. At what period the term stannum was adopted for tin is uncertain. As shown by Beckmann (Hist. of Inventions II, p. 225), it is used as early as the 6th century in occasions where tin was undoubtedly meant. We may point out that this term appears continuously in the official documents relating to Cornish tin mining, beginning with the report of William de Wrotham in 1198.