OBJECTS FOK POLABIZED LIGHT. 



44 



Objects for Polarized Light. — The application of the polar- 

 izing apparatus to the compound microscope was first made 

 by Henry Fox Talbot, Esq., since which it has been much 

 employed by Sir David Brewster, Sir John HerscheU, and 

 other great authorities ; and as it now forms so important an 

 instrument for the determination of the slightest differences 

 of density in the most delicate structures, its use to the 

 anatomist and chemist is indispensable ; but for those who may 

 only wish to know the kinds of objects that show the richest 

 tints of colour when viewed by polarized light, the follow- 

 ing is a list of such as are usually sold by the preparers of 



