278 On the Affinity existing between 



15 grains of the above charcoal and 200 of oxide of iron 

 gave a metallic button weighing 51 grains (equal to 25f per 

 cent, from oxide of iron). 



83| grains of raspings, as requisite to form the above 

 quantity of charcoal, and 200 grains of oxide of iron, being 

 mixed and perfectly reduced, afforded a button of iron that 

 weighed (equal to 34{ per cent.) - 69 grains. 



Revived by means of charcoal 5 1 



Increase (equal to 9 per cent.) 1 8 



Experiment XXI. 

 Charcoal prepared from Bragnut of the specific gravity 



pf 1-1009, 



Composed of oxide of carbon 96-250 

 Ashes * 3*750 



100 parts, 



15 grains of this charcoal were mixed with 200 grains of 

 pxide of iron, and the result by fusion was a metallic button 

 weighing 36 grains (equal to 18 per cent.). 



45 grains of bragnut were found equivalent to form 15 

 grains of charcoal. These in a state of raspings, and 200 

 grains of oxide of iron, were mixed together and fused; the 

 result was a metallic button of iron weighing (equal to 2 J 

 per cent.) 42 grains. 



Revived by means of charcoal 36 



Increase (equal to 3 per cent.) 6 



From the result of these experiments, it will appear at 

 one glance, that the extent and purity of the carbonaceous 

 matter in charcoals do not at all depend upon the absolute 

 quantity of combustible matter they contain respectively. 



The largest portion of revived iron is obtained with char- 

 coal of birch, the quantity of combustible matter in which 

 (by Experiment XVIII.) is 89'681. Iron revived 62 grains. 

 Combustible matter in oak 98*135 - 54 



In ash 95*725 - 54 , 



In, walnut 96*048 - 30 



This 



