156 LETTEES ON NATURAL MAGIC. 



it would be necessary to place the lantern in another 

 apartment like the mirror in Fig. 4, and to throw the 

 magnified pictures on a large plate of ground glass, or a 

 transparent gauze screen, stretched across an opening 

 E F, Fig. 4, made in the partition which separates the 

 spectators from the exhibitor. The images might, like 

 those of the concave mirror, be received upon wreaths of 

 smoke. These images are of course always inverted in 

 reference to the position of the painted objects ; but in 

 order to render them really erect, we have only to invert 

 the sliders. The representations of the magic lantern 

 never fail to excite a high degree of interest, even when 

 exhibited with the ordinary apparatus ; but by using 

 double sliders, and varyin^their movements, very striking 

 effects may be produced. A smith, for example, is made 

 to hammer upon his anvil, a figure is thrown into the 

 attitude of terror by the introduction of a spectral appa- 

 rition, and a tempest at sea is imitated, by having the 

 sea on one slider, and the ships on other sliders, to which 

 an undulatory motion is communicated. 



The magic lantern is susceptible of great improvement 

 in the painting of the figures, and in the mechanism and 

 combination of the sliders. A painted figure which ap- 

 pears well executed to the unassisted eye, becomes a mere 

 daub when magnified 50 or 100 times ; and when we 

 consider what kind of artists are employed in their execu- 

 tion, we need not wonder that this optical instrument has 

 degenerated into a mere toy for the amusement of the 

 young. Unless for public exhibition, the expense of 

 exceedingly minute and spirited drawings could not be 

 afforded ; but I have no doubt that if such drawings were 

 executed, a great part of the expense might be saved by 

 engraving them on wood, and transferring their outline 

 to the glass sliders. 



A series of curious representations m ight be effected, 



