NATURAL PHILOSOPHY. 189 



After mounting, the tissue, with paper attached, is placed in 

 water of about 100 Fahr. The water presently begins to dissolve 

 away the non-solarized portions of the gelatin, and in a few minutes 

 the picture is fully disclosed. It is, however, advisable not to hurry 

 the operation, but to give the water ample time to dissolve out the 

 bichromate. It is also advisable to change the water three or four 

 times. Leave the prints about two hours in the water. Where the 

 picture has been over-exposed, longer immersion and hotter water 

 will, in a great degree, rectify the mistake. Before finally removing 

 the prints from the water, brush their surface lightly with a broad 

 camel-hair brush ; and, after taking them out, pour a stream of water 

 over them to remove any loosely adherent particles of foreign matter 

 that may by accident have got attached to the surface. The prints 

 may then be hung up to dry, and are finished by being mounted on 

 card-board and rolled, in the usual manner. 



" Diamond Cameo " Photographs. We copy the following article de- 

 scribing a new style of photograph, from the London Photographic News. 

 We have frequently heard the opinion expressed of late, that the 

 "carteomania" was -on the wane, that everybody hid obtained his card 

 picture, that the albums were full, and the public beginning to be sated. 

 No doubt this is, in some quarters, to some extent true. The question 

 has been asked, "What will be the next fashion?" In answer to this 

 question, solar camera pictures or other enlargements, have been doubt- 

 fully mentioned. These, it is very probable, will come into increased 

 demand : but the demand car never become a rage at all similar to that 

 which has existed during the last few years for card pictures. The price 

 and size at once preclude the possibility. To take the place of cards, for 

 which the demand begins to flag, the picture must be as cheap and as 

 easily exchanged and preserved, and at least as pretty. A novelty we 

 have to announce more than fulfils these conditions. 



This novelty, brought out by Mr. R. Window of London, under the 

 name of the "Diamond Cameo Photograph," is of the size of an ordi- 

 nary card, and contains four portraits, each giving a different view of the 

 face. Each portrait consists of a bust about an inch long, and three- 

 quarters of an inch wide: two are side by side in the middle of the 





 card, and two at the top and bottom arranged in this order 0. The 







top and bottom generally consist of a front face view and a three-quarter 

 face view ; whilst the others consist either of two entire profiles, one of 

 the left and one of the right side of the face, or of a profile of one 

 side and a | view of the other ; but of course, much variety in this 

 respect is possible. But the especial peculiarity, and that which gives 

 the cameo effect of the picture, is yet to be described : the oval con- 

 taining each bust is punched into relief, so as to have a convex surface. 

 The effect of this in giving the illusion of roundness and relief to the 

 whole image, cannot be readily imagined by a person who has not seen 

 it. It is difficult at first glance to believe that the features have not a 

 special relief of their own, and the cameo effect is perfect. 



Such a style of portraiture has many real charms and points of in- 

 terest, besides that of novelty. Almost all the artistic difficulties which 

 beset the photographer are got rid of. The graceful arrangement of 



