^ 2. — Application of Photography to Illustrations of Natural 

 History. With two figures printed by the Albert and Wood- 

 bury Processes. 



No attempts have thus far been made to apply the comparatively 

 new processes of carbon printing to general illustrations of Natural His- 

 tory, though excellent figures of microscopic preparations have been 

 printed by carbon processes by Deane, "Woodward, and others. The 

 lithographic plate3 of many memoirs on natural history have been 

 made up with the assistance of photographs, but the want of perma- 

 nence of the common photographic prints has prevented their use be- 

 yond that of auxiliaries to lithography. The rapid progress made in 

 carbon printing by the Woodbury and Albert processes promises to 

 furnish us, within a short time, the means for direct application of pho- 

 tography to illustrations of natural history, and these new methods of 

 printing are likely to replace to a great extent the ordinary litho- 

 graphic plates. 



The accuracy of a photographic illustration is of course far beyond 

 that of an engraving or lithograph, and as soon as a few practical 

 difficulties of printing the separate figures of a plate at one impression 

 are overcome, we shall be able to illustrate our memoirs accurately and 

 economically, and give figures with an amount of detail which the great 

 expense of engraving or lithographing would usually make impossible, 

 even were it mechanically practicable. 



The accompanying plates are fair specimens of what can be obtained 

 by the Albert and by the Woodbury processes, and give a good idea 

 of the character of the two modes of printing; the one imitating a 

 common photographic print, the other a lithograph. These figures are 

 taken from the illustrations of my forthcoming " Revision of the Echini." 

 The one is a figure (natural size) of Echinocidaris punctidata Desml. 

 from South Carolina, printed by the Albert process ; the other, a sec- 

 tion (slightly reduced) of Laganum decagonalis Less, from Hong Kong, 



