Account of an examination of Fused Charcoal. 2935 
certaining its comparatiue density with sulphuric acid, in 
which liquor is sunk. 
The fused charcoal consisted of one large, and one small 
globule, connected together by a thread, or thin bar of the 
same material, and resembled a double headed shot; ex- 
ternally its colour was black, and without lustre, and was 
perfectly opaque. It weighed 2.5 centigrammes or 0.385 
of a grain. 
In the first experiment it was heated red hot by a blow- 
pipe in a silver spoon with caustic potash, which had no 
action upon it; for when well washed and dried, the 
weight remained the same. 
It was then put into an agate mortar, pressed, and struck 
with considerable force ; finding it yielded without break- 
ing, and observing lhat it received a polish, it was exam- 
ined and found to resemble iron. To confirm the analogy, 
it was next tried witha file, which acted upon it as it 
would on soft steel or iron ; after this it was subjected to 
a magnet, to which it readily attached itself; and lastly 
with a hammer ; by its great malleability conjoined with 
the characters just mentioned, it proved its identity with 
iron. 
The fused charcoal was next subjected to the action of 
nitric acid in a small platina capsule, there was no effect 
till the acid was heated, it then attacked the mass, very 
violently disengaging nitrous fumes, and separated it into 
several pieces ; although fresh additions of nitric acid were 
made, yet the whole did not dissolve. The unattacked 
part was separated from the liquor, and examined with a 
microscope; it still exhibited the same appearance and 
still was magnetic. However, by a further division of the 
substance, it was all dissolved by nitric acid, except one 
small piece reserved for exhibition. 
The nitric liquor was evaporated to dryness ; muriatic 
acid and water were then added to dissolve the iron, which 
took up the whole of it, leaving a small quantity of whitish 
matter, from which the liquor was separated by decanta- 
tion; this matter resembled silex, the quantity however, 
was too small to ascertain correctly its nature, for it weigh- 
ed no more than 0.0025 gramme. 
Ammonia added to the liquor, gave the reddish brown 
* precipitate of hydrate of per oxide of iron; separated from 
