_Pompholyx_ was the name given to oxide of zinc, sublimed by the combustion of the zinc which exists in brass. _Spodos_ seems to have been a mixture of oxides of zinc and copper. There were different varieties of it distinguished by various names.[45]
5. Iron exists very rarely in the earth in a metallic state, but most commonly in the state of an oxide; and the processes necessary to extract metallic iron from these ores are much more complicated, and require much greater skill, than the reduction of gold, silver, or copper from their respective ores. This would lead us to expect that iron would have been much longer in being discovered than the three metals whose names have been just given. But we learn from the Book of Genesis that iron, like copper and gold, was known before the flood, Tubal-cain being represented as an artificer in copper and iron.[46] The Hebrew word for iron, לזרב (_barzel_), is said to be derived from רב (_bar_), bright, לזנ (_nazal_), to melt; and would lead one to the suspicion, that it referred to _cast_ iron rather than _malleable_ iron. It is possible that in these early times native iron may have existed as well as native gold, silver, and copper; and in this way Tubal-cain may have become acquainted with the existence and properties of this metal. In the time of Moses, who was learned in all the wisdom of the Egyptians, iron must have been in common use in Egypt: for he mentions furnaces for working iron;[47] ores from which it was extracted;[48] and tells us that swords,[49] knives,[50] axes,[51] and tools for cutting stones,[52] were then made of that metal. Now iron in its pure metallic state is too soft to be applied to these uses: it is obvious, therefore, that in Moses’s time, not only iron but steel also must have been in common use in Egypt. From this we see how much further advanced the Egyptians were than the Greeks in the knowledge of the manufacture of this most important metal: for during the Trojan war, which was several centuries after the time of Moses, Homer represents his heroes as armed with swords of copper, hardened by tin, and as never using any weapons of iron whatever. Nay, in such estimation was it held, that Achilles, when he celebrated games in honour of Patrocles, proposes a ball of iron as one of his most valuable prizes.[53]