MIRRORS OF VARIABLE CURVATURE. 



171 



and it may also be applied to mirrors of variable curvature, 

 which produce different kinds of distortions from different 

 parts of their surfaces. 



By employing a mirror whose surface has a variable 

 curvature like ABC, Fig. 13, we obtain an instrument 

 for producing an endless variety of caricatures, all of 

 which are characterized by their resemblance to the 

 original. If a figure M N is placed before such a mirror, 

 Fig. 13, 



it will of course appear distorted and caricatured ; but even 

 if the figure takes different distances and positions, the 

 variations which the image undergoes are neither suffi- 

 ciently numerous or remarkable to afford much amusement. 

 But if the figure M N is very near the mirror, so that new 

 distortions are produced by the different distances of its 

 different parts from the mirror, the most singular carica- 

 tures may be exhibited. If the figure, for example, bends 

 forward his head and the upper part of his body, they 

 will swell in size, leaving his lower extremities short and 

 slender. If it draws back the upper part of the body, and 

 advances the limbs, the opposite effect will take place. 

 In like manner different sides of the head, the right or 

 the left side of it, the brow or the chin, may be swelled 



