2|8 On the Affinities of 



that by carbonating the product a larger quantity by weigh? 

 would be obtained. 



X. 200 grains or* oxide, 

 100 of carbon. 



. This proportion of mixture was found but partially fusi- 

 ble. A considerable portion of iron was revived in large 

 aud small elobules beautifully carburated. Part of the mo- 

 lecular of the oxide had lost its oxygen, and was either re- 

 solved into an imperfect carburet with the charcoal, or into 

 minute malleable grains of iron. 



XI. 400 grains of oxide, 

 200 - — - of charcoal. 



Although the proportions in this experiment were ffc£ 

 same as in the former, yet a perfect reduction was effected t 

 and a fine button of carbonated metal obtained which 

 weighed - - •* - 280 grs. 



: Globules thrown up in the ebullition of the 



metal - - - - 12 



Equal to 73 per cent* 295 



The under surface of, the product now obtained was richly 

 carburated, the top. plain and smooth. The fracture open 

 and gray, resembling No. I, (or smooth-faced) pig iron. 



The different*results of these two last experiments are one 

 of the many instances which occur in this department oi 

 metallurgy, where the perfection of the operation depends 

 more upon the quantity of matter used than the direct pro- 

 portions of the mixture. 



The deductions which are liable to be made, arising from 

 this source of error, are sometimes most erroneous, and 

 frequently beyond belief. For example : 



XII. 1750 grains of oxide, 



87-J- — of charcoal, or 1 -20th. 



This mixture was fused into a dead ponderous glass of 

 ironXvherein no trace of revived metal could be found : now 

 in Experiment IV, the same proportion of mixture yielded 

 5 per cent, of iron. Again, 



XIII. 1750 grains of oxide, 



175 — ' — of charcoal, or l-10th. 

 The fusion of this mixture afforded a black, shining, 

 heavv glass, without the most minute particle of revived 

 metal. In Experiment V, with the same proportions of 

 oxide and carbon, 28 per cent, of iron was revived, 



XIV. 1 750 grains of oxide, 



0.50 — — of charcoal* or l-7th. 



