82 On the j4ffinities of 



skinned button oF metal was obtained which was found to 

 weish 17 arains, and equal to 4J- per cent. 

 L.xp. IV. 400 grains of raw ironstone, 



40 of carbon. 



The result of the fusion of this compound was a shining 

 pearly coloured glass. A minute hollow sphere of glass 

 in cooling reared itself upon the surface: this was quite 

 transparent, and became iniuiediatclv filled with a snmky 

 blue vapour. It then burst with a fine flash of light, as 

 happened in the former experiment. 



The metallic product consisted of one button of while 

 cas.t iron and five cavburated globules, weighing in all 32 

 grains; and equal to S per cent. A large portion of char- 

 coal remained untaken up, and symptoms of general in- 

 fusibility were evident from the nature ot" the glass. To 

 correct this, and by the effects oF the addition oF calcareous 

 to siliceous ironstone, the following experiment was made: 

 luxp. V. 400 grains of raw ironstone, 



40 of charcoal, 



110 of chalk. 



The reduction of this mixture was complete. The whole 

 of the charcoal had disappeared and a dark green glass ob- 

 tained, which in ihin fragments possessed a little transpa- 

 rency. A metallic button and a few small globules were 

 obtained, which weighed 70 grains, equal to l7Jr per cent. 

 Increase of metal in consequence of the addition of chalk 

 .,38 grains, or 9^ per cent. 



. Exp. VI. 400 grains of raw ironstone, 



50 of charcoal, or l-8th. 



140 of chalk. 



The result of this experiment was a ver\' perfect fusion, 

 A wavy green glass whitish upon the surface was obtamed, 

 and possessed of more transparency than the foruicr. The 

 whole of the charcoal had disappeared, and there was found 

 revived a button of crude iron weighing y6 grains : equal 

 to 24 per cent. 



Exp. VII. 400 grains of raw ironstone, 



60 of charcoal, nearly I -7th. 



This mixture was exposed to a heat of 160° Wedsewood. 

 The result was a rough blackish gray honeycombed mass, 

 covered with globules of bright cast iron. A large propor- 

 tion of charcoal remained untaken up. The whole mass 

 had sunk, but had not entered into fusion. 



The same experiment was repeated with 250 grains of 

 chalk. Only 18 per cent, of iron was revived. A consi- 

 derable 



