LOOKING THROUGH A SOLID BRICK 159 



In truth, however, the observer looks round the brick 

 instead of through it, and this he is enabled to do by means 

 of four mirrors ingeniously arranged as shown in the en- 

 graving. As the mirrors and the lower connecting tube 

 are concealed, and the upright tubes supporting the pre- 

 tended telescope, though hollow, appear to be solid, it is 

 not very easy for those who are not in the secret to dis- 

 cover the trick. 



Of course any number of "fake" explanations are given 

 by the showman who always manages to keep up with the 

 times and exploit the latest mystery. At one time it was 

 psychic force, then Roentgen or X-rays ; lately it has been 

 attributed to the mysterious effects of radium ! 



This illustration is more properly a delusion ; there is no 

 illusion about it. 



