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]
“Then hurl’d the hero, thundering on the ground,
A mass of iron (an enormous round),
Whose weight and size the circling Greeks admire,
Rude from the furnace and but shaped by fire.
This mighty quoit Ætion wont to rear,
And from his whirling arm dismiss’d in air;
The giant by Achilles slain, he stow’d
Among his spoils this memorable load.
For this he bids those nervous artists vie
That teach the disk to sound along the sky.
Let him whose might can hurl this bowl, arise;
Who farthest hurls it, takes it as his prize:
If he be one enrich’d with large domain
Of downs for flocks and arable for grain,
Small stock of iron needs that man provide,
His hinds and swains whole years shall be supplied
From hence: nor ask the neighbouring city’s aid
For ploughshares, wheels, and all the rural trade.”
The mass of iron was large enough to supply a shepherd or a ploughman with iron for five years. This circumstance is a sufficient proof of the high estimation in which iron was held during the time of Homer. Were a modern poet to represent his hero as holding out a large lump of iron as a prize, and were he to represent this prize as eagerly contended for by kings and princes, it would appear to us perfectly ridiculous.
Hesiod informs us, that the knowledge of iron was brought over from Phrygia to Greece by the Dactyli, who settled in Crete during the reign of Minos I., about 1431 years before the commencement of the Christian era, and consequently about sixty years before the departure of the children of Israel from Egypt: and it does not appear, that in Homer’s time, which was about five hundred years later, the art of smelting iron had been so much improved, as to enable men to apply it to the common purposes of life, as had long before been done by the Egyptians. The general opinion of the ancients was, that the method of smelting iron ore had been brought to perfection by the Chalybes, a small nation situated near the Black Sea,[54] and that the name chalybs, occasionally used for steel, was derived from that people.
Pliny informs us, that the ores of iron are scattered very profusely almost every where: that they exist in Elba; that there was a mountain in Cantabria composed entirely of iron ore; and that the earth in Cappadocia, when watered from a certain river, is converted into iron.[55] He gives no account of the mode of smelting iron ores; nor does he appear to have been acquainted with the processes; for he says that iron is reduced from its ore precisely in the same way as copper is. Now we know, that the processes for smelting copper and iron are quite different, and founded upon different principles. He says, that in his time many different kinds of iron existed, and they were stricturæ, in Latin a stringenda acie.
That steel was well known and in common use when Pliny wrote is obvious from many considerations; but he seems to have had no notion of what constituted the difference between iron and steel, or of the method employed to convert iron into steel. In his opinion it depended upon the nature of the water, and consisted in heating iron red-hot, and plunging it, while in that state, into certain waters. The waters at Bilbilis and Turiasso, in Spain, and at Comum, in Italy, possessed this extraordinary virtue. The best steel in Pliny’s time came from China; the next best, in point of quality, was manufactured in Parthia.
It would appear, that at Noricum steel was manufactured directly from the ore of iron. This process was perfectly practicable, and it is said still to be practised in certain cases.
The ancients were acquainted with the method of rendering iron, or rather steel, magnetic; as appears from a passage in the fourteenth chapter of the thirty-fourth book of Pliny. Magnetic iron was distinguished by the name of ferrum vivum.
When iron is dabbed over with alumen and vinegar it becomes like copper, according to Pliny. Cerussa, gypsum, and liquid pitch, keep it from rusting. Pliny was of opinion that a method of preventing iron from rusting had been once known, but had been lost before his time. The iron chains of an old bridge over the Euphrates had not rusted in Pliny’s time; but a few new links, which had been added to supply the place of some that had decayed, were become rusty.
It would appear from Pliny, that the ancients made use of something very like tractors; for he says that pain in the side is relieved by holding near it the point of a dagger that has wounded a man. Water in which red-hot iron had been plunged was recommended as a cure for the dysentery; and the actual cautery with red-hot iron, Pliny informs us, prevents hydrophobia, when a person has been bitten by a mad dog.