494 ON THE ABSORPTION OF LIGHT, ETC. 



able of being transmitted with any considerable intensity 

 to even moderate distances. This strikes me as ob- 

 viously analogous to the ready transmissibility of a ray 

 polarized in one certain direction, through a tourmaline 

 or other absorbing doubly-refracting crystal, while the 

 oppositely-polarized ray (whose vibrations are rectangu- 

 lar to those of the first) is rapidly absorbed and stifled, 

 i.e., dispersed, by the agency of the colouring matter 

 which acts the part of the air in Mr Wheatstone's experi- 

 ment, and self-neutralized by the opposition of its sub- 

 divided portions as above explained. 



SLOUQH, October 19, 1833. 



