82 ADDRESS TO THE BRITISH ASSOCIATION, 1881. 



which were formerly wasted ; and the temperature now 

 practically in use is as much as 1,400, or even more: 

 the result is a very great economy of fuel and an in- 

 crease of the output. For instance, in 1830. a blast 

 furnace with the cold blast would probably produce 

 130 tons per week, whereas now, 600 tons a week are 

 readily obtained. 



Bessemer, by his brilliant discovery, which he first 

 brought before the British Association at Cheltenham 

 in 1856, showed that Iron and Steel could be produced 

 by forcing currents of atmospheric air through fluid pig 

 metal, thus avoiding for the first time the intermediate 

 process of puddling iron, and converting it by cementa- 

 tion into steel. Similarly by Siemens' regenerative 

 furnace, the pig metal and iron ore is converted directly 

 into steel, especially mild steel for shipbuilding and 

 boilers ; and Whitworth, by his fluid compression of 

 steel, is enabled to produce steel in the highest condition 

 of density and strength of which the metal is capable. 

 These changes, by which steel can be produced direct 

 from the blast furnace instead of by the more cumber- 

 some processes formerly in use, have been followed by 

 improvements in the manipulation of the metal. 



The inventions of Cort and others were known long 

 before 1830, but we were then still without the most 

 powerful tool in the hands of the practical metallurgist, 

 viz., Nasmyth's steam-hammer. 



Steel can now be produced as cheaply as iron was 

 formerly ; and its substitution for iron as railway 

 material and in shipbuilding, has resulted in increased 

 safety in railway travelling, as well as in economy, 

 from its vastly greater durability. Moreover, the en- 



