Tin is first known in a piece of bronze rod from Medum, of the IIIrd dynasty. But this was only a freak, and bronze did not come into use till about 1600 B.C., probably introduced from Hungary, as we have noticed. At about 1400 B.C. there is a finger-ring of pure tin, known by its crackling when bent. The metal is, however, scarcely known separate otherwise. Antimony occurs in the form of beads about 800 B.C.; as it was familiar to the Assyrians also, it may have been traded from them. Iron working is an important subject in the history of culture, and the appearances of this metal in Egypt are curiously sporadic. The notion, often suggested, that it might rust away and disappear, is absurd; nothing is more permanent and noticeable than iron rust. The early examples are: (1) a piece of sheet iron said to be found between the stones of Khufu’s pyramid; (2) a lump of iron found wrapped up with copper axes of the VIth dynasty form, and placed at the corresponding level in the foundations of the Abydos temples; this is absolutely certain and not open to any doubt; (3) iron ferules said to be found in the masonry of a pyramid at Dahshur; (4) an iron falchion said to be found beneath the base of a statue of Ramessu II. The certainty about the second example--which was found by trained workmen, levelled at the time, and is stuck together with tools of known date--prevents our needing to hesitate about accepting the less precise authentication of the other examples. Yet iron continued so scarce until about 800 B.C. that we find then a thin iron knife with a handle of bronze cast on it as being the cheaper metal. The explanation of this intermittent use of iron lies in an observation of Professor Ridgeway’s, that all the sites of native iron in the world are where carboniferous strata and ironstone have been heated by eruptions of basalt, and thus produced iron by natural reduction of the ore. Exactly this combination is found in Sinai. Carboniferous sandstone has beds of pure black haematite with it, and a thick flow of basalt has extended over the country. Probably, therefore, occasional pockets of native iron were found there by the Egyptians at long intervals, and thus the use of it was intermittent.