684 



DIORAMA. 



fig. 2 



Fieure 1. represents a sectional elevation of the 

 building which includes two pictures, A shows a 

 saloon to receive the spectators, with benches for 

 seats, &c., the walls of which are elegantly decorated 

 with drapery and painted devices, resembling the 

 inside of a marquee ; while the ceiling, which is 

 slightly raised, is ornamented with a transparent 

 painting, through which is admitted a very obscure 

 degree of light from a skylight above. B is one of 

 the pictures suspended from above, and kept in a 

 due degree of extension by numerous small weights 

 attached to its bottom and sides, the latter of which 

 are suspended by means of cords passing over several 

 small pulleys, fixed to a stationary rail, not shown in 

 the diagram. Between the back of the picture and 

 the window, D (the panes of which are of ground 

 glass) are hung several coloured transparent blinds, 

 arranged on fines in such a manner as to be mov- 

 able up and down, in order to pass by and overlay 

 each other ; and the number and colour of which 

 must be determined by the judgment and skill of the 

 artist, and the nature of the picture. E shows a large 



skylight in the roof of the picture room, for the rays 

 of light to fall downwards on the surface of the pic- 

 ture ; the panes of this window likewise are of 

 ground glass, and it is also furnished with a sort of 

 transparent coloured blinds, some of which are shown 

 at F F. These move upon hinged joints, fixed to 

 their uppermost ends, so as to be capable of moving 

 into the position indicated by the dotted lines, there- 

 by permitting the rays of light to fall without ob- 

 struction on the picture, but when they are raised 

 up as shown in the diagram, they intercept a part 

 of the light ; and, when drawn closely up, they can 

 be made to close up the window entirely, and there- 

 by cause all the rays of light to pass through the 

 coloured shades before reaching the picture, and 

 thus produce a great variety of shades, and tints, and 

 combinations, over the face of the picture. 



The coloured blinds are moved by cords, or lines, 

 attached to them, and carried over small pulleys near 

 the top of the building, from which they descend, 

 and are affixed to a long lever, or balance, G H, 

 which moves upon a centre or fulcrum at A. Thii 



