1 8 2 HER OES OF INVENTION AND DISCO VER Y. 



carbon and silicon. To reduce this to a state of malleable iron, 

 two methods are employed. One, the older, consists in the 

 exposure of the melted pig-iron in a finery or hearth to the 

 highly oxiding action of a blast of atmospheric air. The other, 

 the modern practice, consists in stirring the melted pig-iron on 

 the bed of a reverberatory furnace, so as to bring each portion 

 of the whole mass successively up to the surface, and allow the 

 oxygen of the air to seize upon and combine with the carbon 

 and silicon, which become separated from the iron in the form 

 of " cinder," leaving the product of the operation malleable or 

 "wrought iron." This last process is termed "puddling," and the 

 invention of it is usually ascribed to Henry Cort, as well as the 

 method of producing bar-iron, by means of grooved rolls instead 

 of by the old process of beating it out by forge hammers. 



As in the case of most inventions, Cort's claim has been 

 disputed; and Dr. Percy, in his work on Metallurgy^ shows 

 that other inventors are at least entitled to share in the merit, 

 more particularly the Craneges of Coalbrookdale, and Peter 

 Onions of Merthyr-Tydvil, both of whose patents preceded 

 Cort's. But it does not appear that the inventions of either 

 the Craneges or Onions were adopted by iron-makers to any 

 large extent, and the merit certainly belongs to Henry Cort of 

 practically introducing the method of puddling and manu- 

 facturing iron now generally followed, and which may be said 

 to have established quite a new era in the history of the iron 

 manufacture. When Cort took out his patent, the quantity of 

 pig-iron produced in England was about 90,000 tons a-year ; 

 in 1866 it was above 4,000,000 tons. It was said in that year 

 that there were no fewer than 8200 of Cort's furnaces in oper- 

 ation in Great Britain alone. 



The story of Henry Cort is well and impartially told by Dr. 



