196 HEROES OF INVENTION AND DISCO VER Y. 



Mr. Babbage was bom in 1790, and died on the i8th of 

 October, 187 1. He was the author of several valuable works. 

 One, "On the Economy of Manufactures and Machinery," 

 published in 1832, has gone through several editions, and been 

 translated into several languages. In it all mechanical processes 

 are classified from the most scientific point of view, and the 

 most interesting examples of the more important kinds of 

 manufactures are described. In addition to this work, we may 

 mention his " Comparative View of the different Life Assurance 

 Societies," his "Differential and Integral Calculus," his "Decline 

 of Science, A Ninth Bridgewater Treatise," and "The Exposition 

 of 1 85 1." 



HENRY BESSEMER 



The invention of the Bessemer process of decarburising pig- 

 iron while in a molten state, by blowing atmospheric air through 

 it, and thereby producing steel, is an interesting stor)^ Mr. 

 Bessemer's discovery was in some measure accidental, like so 

 many other discoveries in the arts. The remarkable thing is, 

 that, taking into consideration the attention paid to the chemis- 

 try of metallurgy of late years, the discovery was not made long 

 ago ; and that it should have been reserved for Mr. Bessemer 

 to make it, who was neither a chemist nor an iron manufacturer. 



About 1856, says a writer in the Quarterly Review, the minds 

 of inventors were running in the direction of improved guns. 

 It was believed that these might be made much stronger if 

 some better material than cast-iron were used; and Mr. 

 Bessemer, like many others, began a series of experiments to 

 solve the problem if he could. He first tried a mixture of cast- 

 iron and cast-steel, the result being a half-decarbonised cast- 

 iron. Guns made oi this metal were found to possess great 



