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10 the larger island to the east (Britain), was known to the Romans as the Insulœ Cassiterides.

Pliny states that the tin is found in grains in alluvial soil, from which it is obtained by washing; but he gives no description of the method of smelting. The Latin word for tin was stannum; it was also known as plumbum album, in contradistinction to lead, which was called plumbum nigrum. Tin was used by the Romans for covering the inside of copper vessels, and was also occasionally employed in the construction of mirrors.

Lead was well known to the Egyptians. In Pliny's time it was mainly procured from Spain and from Britain (Derbyshire). Leaden pipes were used by the Romans for the conveyance of water, and sheet lead was employed by them for roofing purposes. The Romans were also aware of alloys of lead and tin. Argentarium was composed of equal parts of lead and tin; tertiarium, used as a solder, consisted of two parts of lead and one part of tin.

Iron, although now the most important of the common metals, was not in general use until long after the discovery of gold, silver, and copper. This was probably due to the fact that, although its ores are relatively abundant and widely distributed, extraction as a metal demanded greater skill and more appliances than were possessed by the earlier races.