80 ELECTROTYPE PROCESSES. 



has been eminently successful in many of these applications. It has 

 also been applied to plates for printing music, and for embossing soft 

 materials, such as leather. By depositing a sheet of copper upon a 

 skin of morocco leather, it may be used for imparting an impression 

 to other skins of leather. 



The printing of music has also been successfully done by electro- 

 typing the plate from a stereotype cast. 



oiyphography. A process, which Mr. Palmer, the inventor, 

 named Glyphography, has been the most successful of the attempts 

 made to apply the electrotype to the art of engraving. The prin- 

 ciple of the invention consists in depositing copper in the grooves or 

 engravings made in a layer of some soft substance spread on a sheet 

 of copper, and covering the whole with a sheet of electrotype copper. 

 The counterpart of the engraving thus produced is used for printing 

 from the same manner as letterpress printers' types or woodcuts. 

 It may therefore be called a mode of stereotyping, with the differ- 

 ence, that the stereotype is made directly from the drawing made 

 by the artist. The drawing, however, must be made in a particular 

 way, which, with the other necessary manipulations, is thus given 

 by Mr. Palmer. 1 



u A piece of ordinary copper plate, such as is used for engraving, 

 is stained black on one side, over which is spread a very thin layer of 

 white opaque composition, resembling white wax both in its nature 

 and appearance : this done, the plate is ready for use. 



" In order to draw properly on these plates, various sorts of points 

 are used (according to the directions here given), which remove, 

 wherever they are passed, a portion of the white composition, 

 whereby the blackened surface of the plate is exposed, forming a 

 striking contrast with the surrounding white ground, so that the 

 artist sees his effect at once. 



"The drawing, being thus completed, is put into the hands of 

 one who inspects it very carefully and minutely, to see that no 

 part of the work has been damaged or filled in with dirt or dust ; 

 from thence it passes into a third person's hands, by whom it is 

 brought in contact with a substance having a chemical attraction 

 or affinity for the remaining portions of the composition thereon, 

 whereby they are heighted ad libitum. Thus, by a careful manipu- 

 lation, the lights of the drawing become thickened all over the 

 plate equally, and the main difficulty is at once overcome : a little 

 more, however, remains to be done. The depth of these non- 

 printing parts of the block must be in some degree proportionate to 

 their width ; consequently, the larger breadths of lights require to 

 be thickened on the plate to a much greater extent, in order to 



1 Glyphography, or engraved drawing, for printing at the type pr'Sss after the 

 manner of woodcuts, 1844. 



