26 ANNUAL OF SCIENTIFIC DISCOVERY. 



entitled to great credit for the ingenuity and perseverance which he 

 has displayed in surmounting them. This remarkable process is prob- 

 ably destined to effect greater changes in the manufacture of iron 

 and steel than many of our iron-masters suspect or would be willing 

 to believe. As a spectacle, there is nothing so startling and, in our 

 view, so magnificent in the whole range of metallurgy. The melted 

 pig iron is allowed to flow from an adjoining cupola furnace into the 

 " converting vessel," which is a circular vessel of iron coated inter- 

 nally with a refractory lining of silica. Several jets of air are then 

 blown in at the bottom, and bubble up through the metal. For 

 a time all goes on quietly, but the temperature gradually increases, 

 and at length a volcanic eruption in miniature suddenly occurs, 

 melted scoriee being projected on all sides with great violence, and 

 which if allowed to escape would inflict serious mischief on any 

 unhappy bystanders. But soon all is again tranquil, and the chamber 

 contains malleable iron in a state of perfect liquidity. This may be 

 tapped out into moulds, and, with special precautions, drawn out into 

 bars, etc. ; but it is apt to be cellular and unsound, effects which Mr. 

 Bessemer has had great trouble in overcoming, if even now he has 

 thoroughly succeeded. Steel is made by introducing into the melted 

 iron in the converting vessel a given quantity of spiegeleisen (spathic 

 iron ore, carbonate of iron), containing a known percentage of car- 

 bon ; and so steel may be produced with any required proportion of 

 carbon. The spiegeleisen dissolves in the iron like sugar in water, 

 rendering the metal more fusible and very liquid. Unfortunately, in 

 the Bessemer process, when pig iron containing phosphorus is operated 

 on, this injurious element is not separated in a sensible degree, as is 

 the case in the process of puddling ; so that only those varieties of pig 

 iron which are free from phosphorus, such as haematite pigs, etc., can 

 be advantageously used. The Bessemer process is now carried on by 

 three large establishments in England, two of which are in Shef- 

 field ; and that it should have succeeded in establishing itself at such 

 a stronghold of prejudice as Sheffield augurs well for its final success. 

 The Sheffield people, however, maintain that good steel for cutlery 

 cannot be obtained by Bessemer's process. Specimens of Besse- 

 mer steel were also sent to the Exhibition from manufactories in 

 France and from Sweden, in which last country it is extensively intro- 

 duced. The process has not yet made its way into Austria. The 

 Prussians have tried it, but failed, and assign as the reason the un- 

 suitable quality of the pig iron employed. It has also been introduced 

 with success in India, for which country it seems preeminently 

 adapted, as suitable pig iron can be readily made there, but where, 

 owin; to the heat of the climate, it is especially desirable to avoid the 

 laborious work of puddling. Mr. Bessemer introduced his process in 

 1855. It was received with approbation by some iron-masters, and 

 with contempt by others ; but it is now evident that it is destined to 

 play an important part in the future history of metallurgy. In the 

 Exhibition, Mr. Bessemer made a very extensive display both of iron 

 and steel produced by his process, and of specimens illustrative of the 

 quality of the metal, as shown by hammering, punching, bending, 

 twisting, stamping, rolling, drawing into tube and fine wire, turning, 

 polishing, etc. A rail was shown, eighty-four pounds to the yard, 



