76 Intelligence and Miscellaneous Articles. 



as I have shown, in the atmosphere o£ the hearth. The cooling and 

 extinction of the gases stops all reaction ; and when the latter are 

 thrown off by the chimney they still contain, as we see, large quan- 

 tities of combustible materials. 



The investigations which I have made for the purpose of taking 

 up a portion of these gases, left hitherto unused, have demonstrated 

 that it is easy to rekindle them by passing them over a fire, at the 

 same time retarding their motion. It was with this view that, in 

 my forges at Saint-Marc (Cote d'Or), I had a furnace of large di- 

 mensions set up to receive the gases as they issued from the gene- 

 rator. On arriving in this furnace, the section of which is more 

 than 3 square metres, the gases lose a large portion of their velo- 

 city, at the same time that they are kindled in passing over a small 

 grating on which coal-cinders, or some combustible of small value, 

 are burned. * - 



The high temperature developed in these conditions is utilized in 

 my works for the annealing of sheet-iron. It is, in fact, known that 

 rolling renders the iron brittle, and that it becomes covered with 

 adherent oxide in the annealing- ovens. By heating the sheets thus 

 altered for twelve hours in cast-iron boxes well closed, arranged in 

 the gas -oven just mentioned, the sheets are found, after complete 

 cooling, to have become perfectly malleable ; and the oxide has dis- 

 appeared, leaving the surfaces clean and bright. This reduction is 

 easily explained if we remember the beautiful researches of MM. H. 

 Sainte-Claire Deville and Troost on the passage of hydrogen through 

 red-hot metals. I have likewise had the honour to communicate 

 to the Academy* various experiments which prove that, on plun- 

 ging a flattened iron tube into a fire, hydrogen passes through its 

 sides, and, accumulating within it, causes it to resume its original 

 form. The gases which have penetrated into the cast-iron box 

 under the influence of the red-hot sides are therefore essentially 

 reducing, and produce in a very short time complete deoxidation of 

 the metallic surfaces. 



In brief, we may conclude from my experiments : — 



1. That the gases issuing from metallurgic fires still contain, 

 even after passing under steam-generators, an important quantity 

 of combustible principles, and that, with the aid of the processes 

 above described, it is easy to kindle them afresh and burn them 

 almost completely. 



2. That the passage of reducing gases through the red-hot me- 

 tallic walls is capable of receiving applications in metallurgy which 

 doubtless will not be limited to the particular case of which 1 have 

 given an account. — Comptes Rtndus de V Academic des Sciences, 

 Nov. 19, 1877, tome Ixxxv. pp. 955-957. 



ON A PILE IN WHICH THE ATTACKABLE ELECTRODE IS OF COKE. 

 BY P. JABLOCHKOFF. 



The coke burned in steam-engines produces work which, trans- 

 * Comptes Rendus, t. lviii. pp. 327, 1057. 



