In 1847, Kelley began, without suggestion or knowledge of any experiments going on elsewhere, to experiment in the processes now known as the "Bessemer," for the converting of iron into steel. To him occurred, as it now appears first, the idea that in the refining process fuel would be unnecessary after the iron was melted if _powerful blasts of air were forced into the fluid metal_. This is the basic principle of the Bessemer process. The theory was that the heat generated by the union of the oxygen of the air with the carbon of the metal, would accomplish the refining. Kelley was trying to produce malleable iron in a new, rapid and effective way. It was merely an economy in manufacture he was endeavoring to attain. To this end he made a furnace into which passed an air-blast pipe, through which a stream of air was forced into the mass of melted metal. He produced refined iron. Following this he made what is now called a "converter," in which he could refine fifteen hundred pounds of metal in five minutes, effecting a great saving in time and fuel, and in his little establishment the old processes were thenceforth dispensed with. It was locally known as "Kelley's air-boiling process." It proved finally to be the most important, in large results, ever conceived in metallurgy. I refer to it hurriedly, and do not attempt to follow the inventor's own description of his constructions and experiments. When he heard that others in England were following the same line of experiment, he applied for a patent. He was decided to be the first inventor of the process, and a patent was granted him over Bessemer, who was a few days before him. There is no question that others were more skillful, and with better opportunities and scientific associations, in carrying out the final details, mechanical and chemical, which have completed the Kelley process for present commercial uses. Neither is there any question that this back-woods iron-making American was the first to refine iron by passing through it, while fluid, a stream of air, which is the process of making that steel which is not tool steel, and yet is steel, the now almost universal material for the making of structures; the material of the Ferris wheel, the wonderful palaces of the Columbian exposition, the sky-scrapers of Chicago, the rails, the tacks, [Footnote: In the history of Rhode Island, by Arnold, it is claimed that the first cold cut nails in the world were made by Jeremiah Wilkinson, in 1777. The process was to cut them from an old chest-lock with a pair of shears, and head them in a smith's vise. Then small nails were cut from old Spanish hoops, and headed in a vise by hand. Needles and pins were made by the same person from wire drawn by himself. Supposing this to be the beginning of the cut-nail idea, _the machine for making them_ would still remain the actual and practical invention, since it would mark the beginning of the industry as such. The importance of the