210 On the Component Parts oj Iron-jlones. 



from the former. Widely different indeed would be the 

 conclufion. He now would have learned that metals are 

 r-ombuftible bodies ; that under certain circumftances iron 

 Is one of the mod inflammable in the group ; that, during 

 its combuftion, it decompofes the air that maintains the 

 eombulKon, and fixes one of its elements in fpite of the 

 powerful affinity exerted upon it by the caloric ; and that 

 by this procefs alone it increafes its volume and weight. 

 The porous mafs of iron-ftone would now be defcribed as 

 having had its iron completely faturated with oxygen at a 

 very high temperature; that an imperfeft ftate of fufion had 

 been the confequence ; and that a combination of thefe 

 circumftances, afting for a confiderable length of time, had 

 volatilifed and carried off a very confiderable portion of the 

 metal. 



On the fame principle would be explained the increafe of 

 weight in the more ponderous piece ; it would then readily 

 be conceived, that the fame affociation of circumftances had 

 not been prefent ; but that the iron had gained in weight 

 by the addition of oxygen at a temperature fhort of fufing 

 and volatilifing the oxyd. 



What I have further to ftate on this fubject fhall be 

 forwarded for the next Number of the Philofophical Maga- 

 zine. In the mean time I fhall fubjoin a few remark? 

 which may be confidered in the light of a 



Pujlfcript to the Paper on the Principles of Iron and Steel. 



In that paper (Phil. Mag. Vol. II. p. 165) I ftated that 

 the carbon which exifts in fteel is in an elaftic or aeriform 

 ftate. In a long feries of experiments which I made on 

 the diffolution of crude-iron and fteel in various acids and 

 in water, I always obtained carbon from the former in a 

 crude concrete form ; but the carbon in fteel always eluded 

 my fearch, and never appeared till fome days afterwards, in 

 the mauaer of a greafy pellicle, \\\\\\ and tranfparent upon 

 A the 



