On the Component Parts of Iron-Jlones . 245 



nufacturing of iron. At fome future period I may fubmit 

 to the manufacturers of iron a double method of preparing 

 iron-flones for- the blaft-furnace ; in which, certainty of 

 operation would be obtained, and in the end moft pro- 

 bably a degree of economy infured equal to that of the 

 prefent mode. 



I would effect this by expofing the iron-flone ftratified 

 with a fmall proportion of coals, in fimply conftructed ovens, 

 entirely covered on the top, except a few fmall funnels to 

 carry off the fmoke and difengaged vapours ; the ignition to 

 be occafioned by a current of flame paffing under a flue in 

 the bottom of the furnace, and conveying combuftion to the 

 fub-ftratified coals. As this operation could be conducted 

 to a phyfical certainty by means of damping the fur- 

 nace inflantaneoufly, as foon as the vapour, &c. had ceafed, 

 or as foon as complete ignition had pervaded the contents, 

 (the duration to be determined by the nature of the iron- 

 ftone,) the relults in this cafe could at all times be depended 

 upon, and the prefent irregular products avoided. A fecond 

 method of depriving iron-ftones of their volatile mixtures 

 would be to expofe them to a confiderible degree of heat, 

 in contact with the duft of pit-coal coaks — as being the molt 

 economical — fhut up from the admiflion. of external air. 

 This would not only deprive them of their acid water, 8cc. 

 but would alfo unfix moft of the oxygen combined with 

 the metal, and afford the iron nearly in a difengaged ftate. 

 Both thefe methods, however, at the prefent time, want the 

 fanclion of approving practice, on an extenfive fcale, to ren- 

 der them ufeful, or worthy of univerfal attention. 



De-oxj'genation of Iron-jlones . 

 This procefs has been long known in part, and its prin- 

 ciples (lb far as underrtood) applied by the metallurgift to 

 deprive the ore, fubjected to the affay-furnace, of its oxygen, 

 in order that the metal might become revived. Its operation 

 is however much more extenfive than what has hitherto 

 R 3 been 



