compared with the living forms, many of them are 

 sadly wanting, indeed. It is as if an ordinary pho- 

 tograph were compared to a motion-picture in 

 color. Particularly is this true of those extremely 

 delicate organisms without a skeleton or hard 

 parts. Where it is at all possible to preserve them 

 as microscope mounts, the process of preparation 

 oftentimes alters their shapes; always it destroys 

 their colors. However, the dead mounted subject 

 has one advantageous feature not shared by the 

 living organism, which lends itself to the inquiry 

 of the microscopist. Methods in microtechnique 

 make it possible to clear opaque tissues; with the 

 aid of selective stains — that is, with dyes which 

 color certain parts, leaving the others transparent 

 — important inner structures can be revealed; and 

 not seldom these are as beautiful to the eye as they 

 are significant to the mind. 



Reluctantly, then, I leave the further allure- 

 ments of the slide-case, and bring forth from its 

 box on a shelf my low-power binocular microscope. 

 Unlike its higher-powered brother, the monocular 

 just abandoned, the binocular with its paired ob- 

 jective lenses is the only instrument allowing true 

 stereoscopic vision. Everything within the range of 



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