Metallurgy of Iron. 21 



again employed for cementation. A small portion of carbon from 

 the decomposition of the oil rests however with the iron, and. at 

 the temperature of low redness, employed near the end of the dis- 

 tillation, appears to have already combined chemically with the 

 metal. This treatment with the bath and distillation, may be re- 

 newed if the carbonization is not sufficient after one operation. 



The cemented sponge is now ground to powder and moulded 

 by hydraulic pressure into small ingots, which may be heated and 

 directly wrought under the hammer, like the compressed iron 

 sponge ; the metal thus obtained may be compared to refined 

 blistered steel. If however the cemented and compressed sponge 

 be fused in crucibles, as in the ordinary process for making cast 

 steel; the .whole of the earthy impurities which may be present, 

 rise to the surface as a liquid slag, which is easily removed, while 

 the fused metal is cast into ingots. In this way, by cementation, 

 and a single fusion, the iron sponge is converted into a cast steel, 

 which is from the mode of its preparation, more uniform in quality 

 than that obtained by the ordinary process, and which was found 

 by the Jury to be of remarkable excellence. 



Such is a brief outline of the methods invented bv Adrien Che- 

 not for the reduction of iron ores, and the fabrication of wrought 

 iron and steel, constituting in the opinion of one eminently fitted 

 to judge the case, (Mr, Leplay, of the Imperial School of Mines, 

 and Commissary General of the Exhibition,) the most important 

 metallurgical discovery of the age. 



The peculiar condition of the iron sponge has enabled the in- 

 ventor to make many curious alloys, some of which promise to be 

 of great importance ; by impregnating it with a solution of bora- 

 cic acid, a peculiar steel is obtained, in which boron replaces car- 

 bon, and by a similar application of different metallic solutions 

 various alloys are produced, whose formation would otherwise be 

 impossible. 



The processes of Mr. Chenot are now being applied to the fabri- 

 cation of steel at Clichy, near Paris, where I had an opportunity 

 of studying in detail the manufacture. The iron ore is imported 

 from Spain, and notwithstanding the cost of its transport, and the 

 high prices of labor and fuel in the vicinity of the metropolis, it 

 appears from the data furnished by Mr.. Chenot to the Jury, that 

 steel is manufactured by him at Clichy, at a cost which is not 

 more than one-fourth that of the steel manufactured in the same 

 vicinity from the iron imported from Sweden. According to Mr. 

 Chenot, at the works lately established on his system by Villa- 



