THE 



AMERICAN 

 JOURNAL OF SCIENCE, &c. 



Art. I. — On Galvanography, or the art of producing from 

 copper plates, formed hy galvanic action, impressions from, 

 designs painted in the style of sepia sketches ; by Prof, von 

 KoBELL. Munich, 1842.* 



Remark by the Editors. — ^Perhaps much of the first portion 

 of this article may seem to some of our readers as redundant, 

 in the present state of knowledge of the application of galvanic 

 electricity to the arts. Mr. Spencer's process of electrography 

 has been long before our readers, (see Vol. xl, p. 157,) and many 

 of the details are similar to those here given. But the peculiar 

 and important application which the art has received in the hands 

 of Von Kobell, demands that his statement of his own processes 

 should be left unabridged. 



Our readers will appreciate the practical value of the memoir. 

 But we would remark, that all the detail of apparatus with dia- 

 phragms of parchment and double cells, is now entirely superseded 

 by the subsequent improvements in the electro-metallurgic art. 

 It is now well known that nothing more is needed in the depo- 

 sition of copper, silver, gold, or other metals, than a simple con- 

 stant battery whose poles terminate in a neutral solution of the 

 metal to be deposited. This simplification of the method, 

 (which has been brought into use since Von Kobell's paper was 



* Kindly translated from the original, by W. G. Lettsom, Esq., for this Journal. 

 Vol. xLviii, No. 2.— Jan.-March, 1845. 29 



