DECORATIVE NATURAL HISTORY WORK. 19 



drying it will be found to have stretched itself into the 

 closest of contact. Precautions should be taken to 

 ensure that it shall remain dry when framed. The 

 effect of several pieces of glass together at the back of 

 the transparency is the same as that of a dull mirror. 

 Silvered glass is delightful, but difficult to prepare. 

 Ordinary looking-glass gives too many reflections, 

 owing to the glass being in front of the reflecting 

 surface. It need hardly be pointed out that carbon 

 prints can be directly transferred to any of the 

 substances referred to as backings, if these have pre- 

 viously received an insoluble substratum of chromated 

 gelatine. For natural history subjects the print is 

 never quite so effective as the backed transparency, 

 perhaps because a matt surface is as " unnatural" ;is 

 a highly polished one. 



The application of carbon transparencies, especi- 

 ally metallic transparencies, to decorative purposes, 

 is of so varied a character that it is impossible 

 to do more than outline its possibilities. A water 

 subject will usually be in good keeping as the surround 

 of a mirror. The figure (p. 120) shows a simple and 

 effective arrangement. It consists of a rectangular 

 sheet of white metal, with seven openings. The large 

 centre one is occupied by the mirror, and the six sur- 

 rounding ones by carbon transparencies of some water 

 subject newts or fish, for instance backed with the 

 same metal as that which composes the frame. The 

 surround of a washing stand "splasher" may be 

 similarly treated. One need not hesitate at working on 



