93 New Optical JSIuchine called the Phantasmascope. 



G H I, a drawer, open at the end I, and covered at the top 

 G7K with tin plate. It is represented in the figure as drawn 

 out al)Out 10 inches. 



ah, a uKjveable stage, 15 inclics by G, which slides freely 

 upon the bottom of the drawer by means of a strong brass 

 rod c a. 



dx, a partition fixed to the stage o/', which is 15 inches 

 long, and reaches nearly to the top of the drawer. 



.r, a circular aperture, 3 or 4 inches in diameter, made 

 near the bottom of the partition, and at equal distances from 

 each end of it. 



x (7, a screen 74^ inches high by 4^, covered with white 

 paper on that side next the mirror. This screen prevents 

 any light, reflected from the end of the drawer, from passing 

 through the aperture x. 



np, part of the cover, fixed as represented in the figure, 

 to prevent the inside of the machine from being seen by the 

 observer. 



When this machine is used, take a painting on glass in 

 transparent colours, place it against the aperture x in the 

 partition on that side next the mirror, and two short candles 

 on the other side, between za and dx. The glass must be 

 perfectly opaque, except that part upon which the figure is 

 painted; then the light which is transmitted through the 

 painting and falls upon the mirror, is reflected into the air 

 where the phantom is formed ; but the phantom is much 

 more beautiful than the painting, as the colouring receives 

 a peculiar delicacy from the glasses. 



When the painting is in the place represented in the 

 figure, the phantom appears without the machine at y ; but 

 if the stage be drawn out to the end of the drawer G H, the 

 pliantom will appear within the machine at r, and very 

 small. A very pleasing effect is also produced from a small 

 painting on paper, or a coloured print put in the place 

 of the painting on glass, with candles on the other side, 

 near b. 



Application 



