Iron Manufacture and Heat Generation1

Abstract

Iron Manufacture and Heat Generation. 1 By Prof. HENRY Loms. rl1HE date and even the place of the first use of is derived from Egyptian mural paintings. All the iron by mankind have never been deter-earlier ones-for example, one from the frescoes of mined; it appears to be generally held that iron Beni-Hassan (Fig. 1), said to date from about was first produced in workable quantity on the southern flanks of the Caucasus, and the date assigned is usually somewhere about 3000 B.c., though for my purpose both the place and t.he exact or even the approximate date are matters of secondary importance. My main object is to indicate that the history of iron manufacture shows it in the light of a consequence of the everincreasing power which mankind gradually learnt to exercise over the production of heat, and I hope to be able to show that the history of iron and the history of heat generation have gone hand-in-hand throughout the ages, and that the former has been absolutely dependent upon the latter. It is certain that, before iron came into use, the metallurgy of bronze was already highly developed. Articles of bronze of the Later Bronze Age show that the art of bronze-founding had already reached a high stage of perfection. The art of making cored castings was undoubtedly known, and it seems probable that even the eire perdue process had been invented. No doubt the simple reduction of metallic iron from its ores would have been well within the capabilities of these primitive metallurgists, but from the simple reduction of the metal to its fashioning into any useful form is quite a far step. Oxide of iron is reducible to the metallic state at a very low temperature, not exceeding 500° C., but the iron so produced is more or less pulverulent and useless for all practical purposes. To weld it into l-L s c 4 FIG. I.-Blowing up the fire by the mouth blowpipe (Egypt). From Wilkinson's "The Ancient Egyptians".