Papers relating to the Fusion of Carbon. 119 
The quantities of fused carbon, with which these experi- 
ments were made, were too limited, to admit of my ascertain- 
ing the ratio of the iron to the carbon; but, the proportion of 
the metal was evidently very minute, being productive only 
of a slight and partial discolouration of the platinum. 
From these experiments, it would seem, that the sub- 
stances examined, are carburets of iron. The copiousness 
of the precipitation with lime water, indicates that the nitrate 
of potash had met with enough carbon in the fused product, 
to generate a considerabie proportion of carbonic acid, which 
combined with the potash, and was afterwards yielded up to 
the lime; while the discolouration of the prussiate of potash, 
and the minuteness of residuum occasioning it, prove, that a 
small proportion of iron existed also in the subject of exam- 
ination. 
I beg leave here to reiterate the opinion advanced at the 
close of my strictures on Prof. Vanuxem’s memoir, that the 
presence of a minute portion of iron, in the projection arising 
on charcoal exposed to galvanic ignition, cannot materially 
diminish the interest excited by the fact, that matter, so fixed 
and infusible, should be thus mysteriously accumulated on 
one pole, at the expense of the other. 
The combustion of the fused product of charcoal. by the 
flame of the compound blowpipe, as mentioned above, de-~ 
monstrates the impropriety of using that instrument, to ob- 
tain such products, agreeably to the course pursued by Prof. 
Vanuxem. 
V. Notice of some recent experiments on Charcoal, Wc. By 
Prof. SittiMan. 
Ever since the publication of the experiments on this sub- 
ject in 1823, L have been anxious to prosecute the inquiry 
further, but have been prevented by want of health, and by 
indispensable duties. Even now, lam not prepared to pre- 
sent that full view of the subject, which is desirable, but a 
few facts may be stated on this occasion. 
I carefully prepared a sufficient quantity of the best maple 
charcoal, by selecting that which had been made from young 
