46 Dr. Schafhaeutl on the Different Species of 
fragment was more rapidly attacked than the bright crystal- 
line fracture of the steel. That most rapidly attacked was 
the before-mentioned adhering drop of steel; a light yellow 
powder was first separated, which partly rose to the surface 
and partly descended to the bottom ; next a gray precipitate 
was generated, which increased until the acid ceased to act 
upon the steel. All parts of the steel fragment which show- 
ed an incipient melting and silver-white colour, retained this 
colour during the action of the acid ; the other parts of the 
outside of the fragments showed a blackened granular forma- 
tion, traversed by white shining needles. 
After having taken the fragment from the acid, I filed the 
surface of the before-mentioned steel drop off, and laid open 
a grayish surface traversed by a venous network, white and 
shining, and much more difficult to be attacked by the file 
than the lower gray and softer parts betwixt the network. 
On pouring fresh acid again over it, the filed surface was soon 
covered with a deep black velvety crust, traversed by a silver 
white elevated network, somewhat similar to the veins in some 
marbles. The interstices between the network, after removing 
this black crust, were found to be filled up with small crystal- 
line needles, and all the white places, showing an incipient 
fusion, which the day before had remained white, disappeared 
partially on the second day, leaving only a few spots like the 
remainder of a skin, which covered a similar composition, 
formed of an aggregation of needles. The faces of the cubical 
crystals seemed also to consist only of a silvery skin, which 
being corroded and eaten through by the acid, showed under- 
neath a granulated texture. A gray precipitate was found on 
the bottom of the glass, distinctly intermixed with a little yel- 
lowish granulated powder. 
A separated cubical piece of the same bar, treated in the 
same manner in a wine-glass, was not very rapidly attacked 
by the acid, but milky streams were observed ascending to 
the surface. Fresh acid was then substituted. The liquid 
soon became milky; a copious white precipitate fell, which 
two hours afterwards assumed a whitish flocky form, and 
only a few small black flocks seemed to be mixed with copious 
yellowish flocks. 
In order to obtain some further information respecting this 
powder, which I considered as silica, I used fragments of the 
size of a pea of a highly-cubical crystallized steel bar, made 
from burnt English iron, prepared after my method ; secondly, 
a granulated fragment of the exterior of the same bar; thirdly, 
a small crystallized sponge-like piece from the belbre-mention- 
ed burnt bar, before its conversion into steel. I put over 
