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 cr3'stallized 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 before-mention- 

 ed burnt bar, before its conversion into steel. I put over 



