Three circumstances contributed to the rise of this greatest of American industries: a new process for cheaply converting molten pig iron into steel, the discovery of enormous deposits of ore in several sections of the United States, and the entrance into the business of a hardy and adventurous group of manufacturers and business men. Our steel industry is thus another triumph of American inventive skill, made possible by the richness of our mineral resources and the racial energy of our people. An elementary scientific discovery introduced the great steel age. Steel, of course, is merely iron which has been refined--freed from certain impurities, such as carbon, sulphur, and phosphorus. We refine our iron and turn it into steel precisely as we refine our sugar and petroleum. From the days of Tubal Cain the iron worker had known that heat would accomplish this purification; but heat, up to almost 1865, was an exceedingly expensive commodity. For ages iron workers had obtained the finer metal by applying this heat in the form of charcoal, never once realizing that unlimited quantities of another fuel existed on every hand. The man who first suggested that so commonplace a substance as air, blown upon molten pig iron, would produce the intensest heat and destroy its impurities, made possible our steel railroads, our steel ships, and our steel cities. When William Kelly, an owner of iron works near Eddyville, Kentucky, first proposed this method in 1847, he met with the ridicule which usually greets the pioneer inventor. When Henry Bessemer, several years afterward, read a paper before the British Association for the Advancement of Science, in which he advocated the same principle, he was roared down as "a crazy Frenchman," and the savants were so humiliated by the suggestion that they voted to make no record of his "silly paper" in their official minutes. Yet these two men, the American Kelly and the Englishman Bessemer, were the creators of modern steel. The records of the American Patent Office clearly show that Kelly made "Bessemer" steel many years before Bessemer. In 1870 the American Government refused to extend Bessemer's patent in this country on the ground that William Kelly had a prior claim; in spite of this, Bessemer was undoubtedly the man who developed the mechanical details and gave the process a universal standing.