716 CATALOGUE OF GRAPHIC ART EXHIBIT. 



15. HYALOGRAPHY. 



Hyalograpliy (from hyalos, glass), etching on glass, properly so called. 

 This is a regular etching process, in which glass is substituted for metal, 

 and fluoric is used instead of nitric or other acid. 



Frame 35. — No. 172, printed directly from the etched glass plate. 



From Aner (1853). 



16. STYLOGRAPHY. 



Stylography (from stylus, au instrument for writing) is a result of 

 the desire to reduce the labor of engraving to a minimum, and to give 

 greater freedom than the graver will allow to the artist, while attaining 

 similar results. The work is done with points upon a softish*black com- 

 position, whitened on the surface. As each stroke of the tool removes 

 the white surface, the artist sees his picture in dark lines upon a light 

 ground, and the qualities of the composition admit of considerable 

 freedom of hand. Electrotyping furnishes the printable plate. The 

 process can be used for both relief and intaglio engraving. 



Frame 35. — No. 173, from a stylographic intaglio plate. From 

 Auer (1853). 



17. CHEMITYPY. 



The design is etched upon a metal plate in the usual way. An easily 

 fusible metal in the molten state is then poured upon it, and after this 

 has hardened it is ground off down to the original plate, the lines in 

 which are now filled. Tbe plate is then exposed to the action of an 

 acid, wliich attacks the harder but not the softer metal, and the lines 

 are thus left standing in relief, producing a block for the type press. * 



Frame 35. — Nos. 174 and 175, chemitype specimens from Auer (1853.) 



18. XEROGRAPHY. 



This process is not described, but from its name, literally " wax writ- 

 ing," it would appear to be similar to that mentioned in the next para- 



* Two processes, of which uo specimens are shown, must at least be mentioued here: 

 Ektypography or Typographic Etching. — This is the reverse of the ordinary 

 etching process. The drawing is made upon a metal plate with a llnid which, after 

 it has dried, resists acids, or it is made through an etching ground, and the lines 

 laid bare are gilt. The spaces between the lines are then bitten away, and the re- 

 sult is a relief block for the type press. The French Gillot and Comte processes are 

 modilicatious of this process. 



Glyphoguaphy. — A plate is etched iu the usual way, and the spaces between the 

 lines are built up by the application to the surface of the plate of quickly drying sub- 

 stances. By electrotyping, a relief block is obtained for the tjj^e press. In a similar 

 process the lines are merely drawn through a ground on a metal plate, without etch- 

 ing, Electrotyping again furnishes the relief block. The name has also been ap- 

 plied to the wax process. See paragraphs lb and 19. 



