On the AffinUles of different Earths for Carlon. 135 



Besults of 4th class, compounded of 



40 parts of oxide, 



20 of chalk, 



20 of clay, 



and 20 of sand. 



Oiiantity of matter used in each experiment 400 grains. 



pel" cent. 



Exp. I. l-30th of carbon yielded 2^ grs. of iron, or 625 

 II. l-20th ditto 35 ditto, or 8-73 



III. i-]5th ditto 58 ditto, or 14^ 



IV. 1-lOth ditto 95 ditto, or 23f 



V. l-7th ditto 111 ditto, or 27f 



This last experiment was a perfect assay. The glass was 

 of a dull flinty colour, considerably transparent, and proves- 

 that under similar circumstanced an ore equally composed 

 of clay, lirae, and silex, will smelt to greater advaatage 

 than one either exclusively united to silex or clay. 

 Results of 5th class, compounded of 

 40 parts of oxide, 



30 of chalk, 



30 of clay, 



Quantity of matter operated upon 400 grains- per cent. 

 Exp. I. l-30th of carbon yielded 7 grs. of iron, or H 

 II. l-20th ditto 



III. l-15ih ditto 



IV. 1-lOth ditto 



V. l-7th ditto unfused. 



Results of 6th class, compounded of 



40 parts of oxide, 



30 of clay, 



30 of sand. 



Quantity of matter operated upon 400 grains. per cent. 

 Exp. I. l-30th of carbon yielded 16 grs. of iron, or 4 

 II. l-20th ditto 30 ditto, or 7J- 



III. l-15th ditto 57 ditto, or 14J- 



IV. 1-lOth ditto unfused. 

 Results of 7th class, compounded of 



40 parts of oxide, 



30 of sand, 



30 of chalk. 



Quantity of matter in each experiment 400 grains. 



per cent. 



Exp. I. 1 -30th of carbon yielded 1 gr. of iron, or -\- 



IT. l-20th ditto 13 ditto, or 3i- 



III. l-15th ditto 40 ditto, or 10 



IV. 1-lOth ditto 103 ditto, or 25^ 



V. l-7th ditto — — 129 ditto, or 32^ 



VI. 1 -5ih ditto unfused from an excess of carbon. 

 14 If 



