Cajl Steel from Bar Iron. 99 



Grains. 



Brought over iopp 

 This mixture was expofed to a violent degree of heat, 

 and in one hour I judged tlie fufion complete. The 

 button obtained was Hiifly poliihed upon its upper 

 furface, and remarkably denie. It Vv-eighed - 1059 



Loft in fufiou 40 

 equal to th part of the original weight of the iron. The 



frafture of the button now obtained was of a fmaller grain 

 than the former, equally regular but lefs brilliant. It drew 

 into {hape equally well under fimilar circumftances with the 

 former, and exhibited the very fame appearances. 



One half of this button was forged into a point, and hard- 

 ened at a high heat for common fteel. I endeavoured to 

 pierce a piece of thick rolled plate iron ; but at the firft blow 

 the point bent upwards, throwing a white fliale and leaving 

 the furface like tin. 



The glafs obtained by the fufion of lime alone in this ex- 

 periment was very different from thai in Nos. 7 and 8. It 

 poflefli:-d a rich grafly green colour, free from air bubbles 

 and very tranfparent. The extra lofs of metal in this expe- 

 riment bcvond that in Nos. 7 and 8. may be accounted for 

 from the infufibility of carbonate without the ufual addition 

 of clay. I have repeatedly found that lime alone, when 

 pure, gradually contrails its bulk, and remains unfufed a 

 confiderable time after the iron has entered into fufion. This 

 naturally expofes the latter to a greater degree of oxidation 

 than when covered by a fufible glafs during the greateft part 

 of the expofure. 



The following experiments were performed with Kilkenny 

 blue marble : Grains. 



Exp. X. Pieces of Swedifli iron weighing - 1 196 



I -3d of Kilkenny marble, or 398 grains. 

 I -3d of Stourbridge clay pot, or 398 grains. 

 There refulted from this mixture, after half an hour'.s 

 expofure, a very fine fufion accompanied by a very 

 perlie6t metallic button of - - 1173 



I.,oft in fufion 23 



equal to — ^-th part of the firft weight of the iron. The 



colour of the glafs now formed was fome fliades lighter than 

 in experiment No. 7. The green was fligiitlv tinged with 

 an amber colour, which difference, nioU probably, arufc from 

 the nature of ihc lime. 



G a The 



