64 president's address — section b. 



of air and steam 9S a powerful means of more rapid oxidation than 

 by air alone, the mixture to be projected upon the surface of the bath 

 of molten iron in the puddling furnace. A little later, in the forties, 

 Reuben Plant is said to have used compressed air alone in this manner, 

 and a similar method was tried at Dowlais and Crom Avon in South 

 Wales for a time, but crowded out by the Bessemer process. A varia- 

 tion held its own for a period, which was the method of Richardson, 

 Plant's former partner, who at first introduced compressed air into 

 the bath by means of a curved hollow rabble through the working 

 doors, and later on by means of a specially built pipe inserted verti- 

 cally through the roof of the furnace. He also proposed to use steam 

 and air alternately, his object, in all endeavors, being the purification 

 of the iron by the removal of sulphur and phosphorus. This, how- 

 ever, did not result to any satisfactory degree, for reasons which are 

 patent to the iron industry now, but were long misunderstood then. 

 Plant (1849) similarly proposed to use steam alone. In 1854 Jas. 

 Nasmyth, of steam-hammer fame, also patented the use of a current 

 of steam introduced below the surface of the metal by means of a curved 

 pipe held in the hand and reaching down to the lowest portion of the 

 bath. He included the employment of air, but appears to have pre- 

 ferred steam. It was claimed that the introduction of steam for from 

 two to five minutes, shortly after the iron was melted, was attended 

 by very beneficial results as far as purification was concerned. But 

 the method was not a siiccess. A far greater oxidation of iron took 

 place than was expected, or could be controlled, and the decomposition 

 of the steam caused a serious lowering of the temperature, which had 

 to be made up by extra firing. The point involved is that sulphur 

 can only very slightly be removed by dissociated steam, and phos- 

 phorus not at all, imder the conditions of the work. The very important 

 absorption of heat in the decomposition of the steam might have been 

 foreseen, but was long in being appreciated. Moreover, Deville had 

 previously shown that iron decomposes steam all the less the higher 

 its temperature is. Even within the puddUng furnace there are tem- 

 peratures at which no decomposition takes place, a fact which makes 

 these attempts towards the removal of sulphur and phosphorus futile. 

 These particular efiorts at purifying pig iron with steam, or with a 

 mixture of air and steam, as remarked, are of some interest. They are 

 the precursors of numerous attempts having the same general object 

 in copper- smelting, with identically the same fruitless results. 



The notion of employing air alone under considerable pressure, 

 in a manner quite distinct from its application as a mere adjunct to 

 the puddling or the refining of iron, does not appear to have arisen in 

 Europe prior to Bessemer's day ; but there is no doubt that, from the 

 purely chronological point of view, the scheme was first conceived in 

 America. I refer only to the general pneumatic principle of treating 

 the substance in a molten condition with a blast of compressed air, 

 and thereby further raising its temperature. It in no degree diminishes 

 Sir Henry Bessemer's deserts, as the first practical working exponent 

 of this principle, that another merits the acknowledgment of having 



