42 On the Manufacture of Bar Iron in India, 



" purified gas flame. The arrangement of the gas oven, 

 " with jets of hot air and hot gas intermixed, obtains a very 

 11 high temperature and perfect combustion, since the turn- 

 " ing of a few cocks allows the fire to be regulated at will, 

 " not only with regard to the intensity of its temperature, but 

 M the chemical nature of the flame ; so as to have a neutral, 

 " an oxidising, or a red active flame." 



15. I haye stated in my last paper, that I had reason to 

 believe the gases produced by combustion in close furnaces 

 held nitrogen in combination and I have adduced some of 

 the circumstances which at first led me to suspect this fact ; 

 but I am unable to make public at present, some of the results 

 of my imperfect investigations, because they are connected 

 with the principles which I have applied in practice in my 

 furnaces, with the true explanation of the composition of 

 cast-iron, and with what I may be allowed to term the 

 theory of " acerification," subjects on which I am anxious to 

 preserve to myself the honor of completely analysing : and 

 which I have long ardently wished to follow out, if I could 

 have succeeded in persuading the government to afford me 

 the slightest assistance in support of my labours. 



16. My surmise on this point is directly contradicted by the 

 analytical examinations of able French chemists, as given by 

 Peclet (Traite- de la Chaleur,) but I think it will be allowed 

 by chemists to be probable, that nitrogen at a high tempera- 

 ture may have the property of combining with carbon and hy- 

 drogen, and also with oxygen : which compound may either be 

 resolved into other gases at a lower temperature, or else that 

 the mode of analysis may have been conducted so as to no- 

 tice quantitatively only known compounds. My own surmises 

 on the subject are not based upon chemical analysis, but on 

 physical effects and phenomena which I have witnessed, and 

 which I maintain could not be produced by carbonic oxide. 



17. I will conclude this paper, by stating, that Mr. Clay's 

 bloomery process and the French gas furnaces may be com- 





