And why should it not have seemed strange when we consider that up to that time fuel had been required in all metallurgical processes. In the old Catalan furnace and the types that preceded it, in the Finery Fire, the Walloon and the several other refining furnaces fuel had to be provided without stint. The lowest proportion that seventy years of experiment and practice had brought about in Cort’s puddling process was one ton of coal per ton of iron, while the blast furnace required at the least four-fifths of a ton of coke for each ton of pig iron produced. [Illustration: KELLY’S FIRST TILTING CONVERTER ] Whether Bessemer, an Englishman of French descent, or William Kelly, an American of Irish descent, of Eddyville, Ky., first conceived the idea of the “pneumatic” process is a moot question. Considerable evidence substantiates the claim that the latter first hit upon the scheme and during the ten years between 1846 and 1856 had considerable success with its development. Perhaps Bessemer had heard of Kelly’s experiments. There is no proof that he did. Whether he did or not, the fact remains that he quite independently and very fully developed the process in England, and with great business sagacity and energy made it the success that it is. As fortune has withheld from Kelly and from this country credit which was deserved, it is desirable to tell briefly the part which he had in the development of this process that with a single furnace converts pig iron into steel at the rate of a thousand tons in 24 hours and first made mild steel available as a building material. In 1846 Kelly, with a brother, bought the Suwanee Iron Works, near Eddyville, Ky. After about a year they encountered the same difficulty that charcoal iron manufacturers usually have encountered—the failure of the supply of fuel. This difficulty Kelly, a better inventor than business man, apparently had not foreseen. His business was threatened unless some other way of refining his iron was found. [Illustration: CRUCIBLE WITH WHICH BESSEMER’S FIRST EXPERIMENTS WERE CONDUCTED ] One day while watching the operation of his Finery Fire he noticed that the blast of air from the tuyère made the molten iron where it impinged very much whiter and apparently hotter than the rest. Like other iron makers, he had always supposed that a blast of cold air chilled molten iron. It appears that Kelly was not long in surmising the truth. In a few days he had rigged up a crude apparatus and made soft iron from which a horseshoe and a horseshoe nail were fashioned by a blacksmith. [Illustration: FIXED CONVERTER OF 1856 WITH SIX TUYÈRES ABOUT THE SIDES ] Being conservatives, Kelly’s customers were not slow in informing him that they did not want iron made by anything other than the “good old process” and he was obliged to accede to their demands or lose their trade.