ELEMENTARY PHOTO-MICROGRAPHY. 



lin. OBJECTIVE. 



Transmitted 

 Light. 



Reflected 

 Light. 

 Dark 

 Ground. 



Polariscope. 



Diatoms. " A " eyepiece. Slow plate. Four minutes. 

 Wing of Fly. Slow plate. One minute. 



Foraminifera. " A " eyepiece. Rapid plate. Ten uinutes. 



Diatom*. Slow plate. " A " eyepiece. Sixteen nainutee. 

 Ditto. Ditto. No eyepiece. Ten minutes. 



Aspartic Acid. No eyepiece. Chromatic plate. Eighteen 

 minutes. 



Jin. OBJECTIVE. 



Transmitted 

 Light. 



Section of Deal. "A 

 minutes. 



eyepiece. Rapid plate. Trn 



Jin. OBJECTIVE. 



Transmitted 

 Light. 



Human Blood. " A " eyepiece. Chromatic plate. Green 

 colour screen. Thirty-five minutes. 



. OIL-IMMERSION. 



Transmitted 

 Light. 



Bacteria. Stained red. " A " eyepiece. No colour screen. 



Chromatic backed plate. Twelve minutes. 

 Ditto, with green colour screen. Thirty minutes. 



How TO PHOTOGRAPH MULTIPLE IMAGES THROUGH 

 THE COMPOUND EYE OF AN INSECT. 



Gosse, in his book " Evenings at the Micro- 

 scope," states that there are 24,000 lenses in the 

 two eyes of a dragon fly. " Every one of these 

 24,000 bodies represents a perfect eye ; every one 

 is furnished with all the apparatus and combina- 

 tions requisite for perfect vision, and there is no 

 doubt the dragon fly looks through them all." 



