NATURAL PHILOSOPHY. 185 



basis for the sculptor's work. The bust or statuette once obtained 

 can be easily multiplied by the ordinary means in use for producing 

 plaster images, or it may l>e copied into marble or bronze to suit the 

 taste and purse of its possessor. By varying the mechanical arrange- 

 ments it may be produced of colossal size, or diminished to an inch in 

 hight. By slight modifications of the process, the portrait may be 

 llattened to the proportions of a medallion or bas relief, or cut into a 

 seal or die, and at the will of the operator may even be distorted to 

 yield a grotesque figure or caricature. The editor of the London 

 Art Journal describes the specimens of photo-sculpture he has exam- 

 ined, as well executed, and possessing, indeed, all the appearance of 

 photographic productions, so correct were the forms and proportions, 

 and so natural was the expression of countenance ; they were, in fact, 

 the very "carte de visite" raised in solid form. The specimens in 

 question, represented the actor, Roger, in the character of the "Proph- 

 et," the Annamite ambassador, the Prince of Aquila, a lady sitting in 

 a Gothic chair, a boy, a girl, and various others. There was also 

 one medallion representing the head, half-size, of the Due de Moray ; 

 all were very perfect in execution. 



IMPROVEMENTS IN PHOTOGRAPHY. 



Photographic Ghosts. Photographers are acquainted with three 

 or four different ways in which secondary images may appear in pho- 

 tographs. In the first place, when a sensitive glass plate has served 

 its turn as a negative as many paper positives as may be needed 

 having been taken from it the film of collodion or other prepared 

 surface is removed from it, and it may then be used for a wholly new 

 photograph. But it is found that, unless great care be used, some 

 faint traces of the former picture still remain, and these may appear 

 as a sort of ghostly attendant upon the figure forming the second 

 picture. One photographer, in endeavoring to utilize an old plate 

 which had fulfilledfcits duty as a negative of the late Prince Consort, 

 could not Avholly erase the image, wash or rub as he might ; there was 

 always a faint ghost of the prince accompanying a'ny subsequent pho- 

 tograph taken on the same plate. Dr. Phipson relates that a friend 

 of his received at Brussels a box of glass plates, quite new and highly 

 polished, each wrapped in a piece of the Independance Beige news- 

 paper ; a lady sat for her photograph, taken on one of these plates, 

 and both the photographer and the lady were astonished to see that 

 her likeness was covered with printed characters, easily to be read, 

 the ghost of apolitical article in fact. In this case actinic rays 

 had done their work before the glass was exposed to the camera. 

 By another mode of manipulation, a photographer may produce a 

 ghost-like effect at pleasure : a sitter is allowed to remain in the focus 

 of the camera only half the time necessary to produce a complete 

 photograph ; lie slips quickly aside, and the furniture immediately 

 behind him is then exposed to the action of the light ; as a conse- 

 quence, a faint or imperfectly developed photograph of the man ap- 

 pears, transparent or translucent, for the furniture is visible appar- 

 ently through his body or head. With a little tact, a really surpris- 

 ing effect may be produced in -this way. As a third variety, one 

 negative may be placed in contact with another, and a particular kind 

 16* 



