Page:A History of Art in Chaldæa & Assyria Vol 2.djvu/347

Metallurgy. 309 native state, partly by the fact that it can be smelted at a comparatively low temperature. Soft and ductile, copper has rendered many services to man from a very early period, and, both in Chaldaea and the Nile valley, he very soon learnt to add greatly to its hardness by mixing a certain quantity of tin with it. Where did the latter material come from ? This question we can no more answer in the case of Mesopotamia than in that of Egypt ; no deposits of tin have yet been discovered in the mountain chains of Kurdistan or Armenia. 1 However this may be, the use of tin, and the knowledge of its properties as an alloy with copper, dates from a very remote period in the history of civilization. In its natural state, tin is always found in combination, but the ore which contains it in the form of an oxide does not look like ordinary rock ; it is black and very dense ; as soon as attention was turned to such things it must have been noticed, and no great heat was required to make it yield the metal it contained. We do not know where the first experiments were made. The uses of pure tin are very limited, and we cannot even guess how the remarkable discovery was made that its addition in very small quantities to copper would give the precious metal that we call bronze. In the sepuchral furniture with which the oldest of the Chaldsean tombs were filled we already find more bronze than pure copper. 2 Lead is rare. A jar of that metal, and the fragment of a pipe dug up by Loftus at Mugheir may be mentioned. 3 It is curious that iron though still far from common, was not unknown. Iron nowhere exists in its native state on the surface of our planet, except in aerolites. Its discovery and elimination from the ore requires more time and effort and a far higher temperature than copper or tin. Those difficulties had already been surmounted, but the smelting of iron ore was still such a tedious operation that bronze was in much more common use. Iron was looked upon as a precious metal ; neither arms, nor utensils, nor tools of any kind were made of it ; it was employed almost exclusively for personal ornaments, such as rings and bracelets. 4 1 On the richness of the metalliferous deposits about the head-waters of the Tigris and Euphrates, see vol. i. pp. 124, 125. 2 Rawlinson, The Five Great Monarchies, vol. i. p. 98. 3 Ibid. 4 Ibid.