different Earths for Carlon. 235 



A metallic button resulted from the fusion of this mix- 

 ture weighing 1 ) S grains ; equal to 28 per cent. 



The surface of the glass was covered with an enamel of a 

 pearly white colour: the fracture however was still black 

 and shining, and in thin fraomenis very opake. 



Exp. VI. 400 grains of raw ironstone, 



80 of carbon, or l-jth. 



There resulted from the fusion of this mixture a large 

 button of v^'hite fractured cast iron weighing - 162 grs. 

 About 50 globules mixed with a small portion of 



untaken up charcoal - - _ - 3 



165 



Equal to 41i- per cent. 



The glass obtained was of a foul brownish rusty colour; 

 but the quantity did not exceed 20 grains^ and was attached 

 to the sides of the crucible only. 



Exp. VII. 400 grains of raw ironstone, 



100 of carbon, or l-4th. 



The result of this was precisely the same as last. The 

 quantity of iron 41^ per cent. The glass the same in quan- 

 tity and in colour. Eight grains of charcoal remained un- 

 taken up. 



Recapitulations of experiments made with the second 

 variety of calcareous ironstone. 



Exp. I. fusion per se, yielded no metal. per cent. 



II. l-30ih of carbon yielded 4 grs. of iron, or 1 



III. l-2(nh ditto '■ ■ ^5 ditto, or 6^- 



IV. 1-lOth ditto 68 ditto, or 17 



V. l-7th ditto 112 ditto, or 28 



VI. l-5th ditto 165 ditto, or4I-i- 



VH. l-4th ditto 165 ditto, or 41^1- 



Thc specific gravity of these three varieties of ironstones 

 was as follows : 



Argillaceous ironstone - - 2-984 



Calcareous, first variety - 3* 124 



Ditto, second variety - - 3*550 



[To be ccntiiueiu] 



XLII. CojH- 



