430 Dr. Schafhaeutl on the JDiffereyit Species of 
the gelatinous silica, and analysed like graphite, as stated in 
the beginning of this treatise, proved to be of the same com- 
position as the graphite B. 
I must here observe, that in fragments broken from the 
outside of the same pig-metal traces only of sulphur could be 
discovered ; that the malleable iron produced from this ac- 
cording to my puddling process was extremely soft, and had 
the peculiar property of welding so easily, that tin-plates rolled 
from it adhered so firmly together by heating them a little 
too much, that it became impossible to separate them ; but 
the great quantity of silicon contained in this iron was ex- 
tremely destructive to the bottom and sides of the puddling 
furnace. 
Let us now return to the residuum of iron (B.); white 
Welsh iron. This residuum was found to weigh 6*77 grains, 
and had a dark brown colour and a very strong unpleasant 
smell, peculiar to hydrogen obtained in this manner from cast 
iron. It was powerfully attracted by the magnet, and traces 
only of aluminum could be found. 
3*13 grains of the dried residuum, heated cautiously in a 
weighed platinum crucible, began to glow around the periphery 
before the crucible became red-hot, and the ignition spread 
from thence very slowly towards the centre. The platinum 
crucible was now removed from the fire, covered with its lid 
and cooled near concentrated sulphuric acid under a bell 
glass. Its weight had increased 0 08 grains, and its colour 
changed from brown to black. On the crucible being again 
placed over the lamp and kept in a red heat for ten minutes, 
its black colour changed into a dirty light red, and its weight 
increased equal to 0*27 
On a third repetition of this ignition .... 0*02 
On a fourth 0*05 
On a fifth 0*00 
0*42 
The whole increase of 6*77 grains would therefore be 
0*9084. 
It was still as powerfully affected by the magnet as pre- 
viously to ignition. A part of this powder, 3*55 grains, heated 
with hydrochloric acid of 1*16 sp. gr., in the same crucible, 
a grayish powder remained, which presented a distinct in- 
terspersion of dull black with white spots, and weighed 0*290; 
after ignition it had gained 0*028 and became perfectly 
white. 
It consisted entirely of silica, for which we reckon 0*1528 
silicon. As the black spots disappeared and it gained 0*028 
