74 LETTERS ON NATURAL MAGIC. 



mirrors or lenses. A fire is lighted, and perfumes 

 and incense are burnt, in order to create a ground 

 for the images, and the beholders are rigidly 

 confined within the pale of the magic circle. 

 The concave mirror and the objects presented to 

 it having been so placed that the persons within 

 the circle could not see the aerial image of the 

 objects by the rays deeply reflected from the 

 mirror, the work of deception was ready to begin. 

 The attendance of the magician upon his mirror 

 was by no means necessary. He took his place 

 along with the spectators within the magic circle. 

 The images of the devils were all distinctly 

 formed in the air immediately above the fire, 

 but none of them could be seen by those within 

 the circle. The moment, however, that perfumes 

 were thrown into the fire to produce smoke, the 

 first wreath of smoke that rose through the place 

 of one or more of the images, would reflect them 

 to the eyes of the spectator, and they could again 

 disappear if the wreath was not followed by 

 another. More and more images would be ren- 

 dered visible as new wreaths of smoke arose, and 

 the whole group would appear at once when the 

 smoke was uniformly diffused over the place 

 occupied by the images. 



The " compositions which diffused noisome 

 odours" were intended to intoxicate or stupify the 

 spectators, so as to increase their liability to 

 deception, or to add to the real phantasms which 

 were before their eyes, others which were the 

 offspring only of their own imaginations. It is 

 not easy to gather from the description what 

 parts of the exhibition were actually presented 

 to the eyes of the spectators, and what parts of it 



