48 
Dr. Schafhaeutl on the Different Species of 
I took afterwards two pieces of iron from the puddling fur- 
nace, one just before the granulated mass began to become 
coherent, and the other just before the iron was ready for 
balling or for being made into balls, in order to bring them 
under the forge hammer. These two samples were treated 
with acids as before. The first sample, weighing 29*89 grains, 
separated a gray powder, and left n black skeleton of the iron, 
which very easily crumbled into powder. The weight of the 
gray powder was 0*421, and the black skeleton weighed 
0*250. 
The second sample, which had been forged and consisted 
of a mixture of grains and fibres, weighing 36*625 grains, left 
grayish-green powder first, and on the acid being changed for 
the third time, it deposited white powder and left also a black 
skeleton, which oxidized very rapidly and was soon converted 
into a brown powder. Concentrated nitric acid would not 
act at all on this remainder, but on the addition of hydrochlo- 
ric acid the powder became of a bright red. The remaining 
powders together weighed 0*8125, and the black skeleton 
0*4531. 
We learn from this that the black remainder increases with 
the progressive advancement from cast iron to that of mal- 
leable, and that the gray powder belongs to the gray granu- 
lation, and the white remainder to the finished fibrous iron. 
The relation of the black remainder to the gray appears to 
be in all cases the same, only that the quantity increases pro- 
gressively towards the finishing of the puddling. 
We gather further from these facts, that the yellow powder 
appears only on using concentrated hydrochloric acid, and 
with that species of iron which nearly approaches steel and 
wrought iron. 
At first I considered the yellow powder to consist of silica 
with a small portion of iron, and with the view of ascertain- 
ing with certainty the correctness of my opinion, I collected 
the yellow residuum of the three before-mentioned specimens 
on a very small filter, and separated as much powder as I 
possibly could. 
The powderretained, afterbeing dried, itslightyellow colour, 
and was neither attacked by acids, except by very concentrated 
hydrofluoric acid ; it became white by heating it on a platinum 
foil, and melted with soda on charcoal before the blowpipe, un- 
der efiervescence, into a transparent globule of a ruby colour, 
which retained its transparency after cooling; a circumstance 
which seems to indicate the presence of silica as well as sul^ 
phur\ the presence of the latter was also ascertained by the 
smell. 
