ELEMENTARY PHOTO-MICROGRAPHY. 



A FEW EXAMPLES OF EXPOSURE. 



3iN. OBJECTIVE. 



Transmitted 

 Light. 



Dark 

 Ground. 



Reflected 

 Light. 



Polariscope. 



Section of Human Tongue. Red. " A " eyepiece. No con- 

 denser. Chromatic plate. One minute. 



Leg of Fly. Brown. Ground-glass interposed between 

 lamp and object to secure sharpness of hairs and 

 reduce the white diffraction effects. " A " eyepiece. 

 Slow plate. Four minutes. 



Polycystina. Slow plate. Webster condenser. " A " eye- 

 piece. Four minutes. 



White Coralline. No eyepiece. Slow plate. Side reflector. 

 Five minutes. 



Tongue of Whelk. No eyepiece. Chromatic plate, 

 minutes. 



Five 



SIN. OBJECTIVE. 



UN. 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 minutes. 



Diatoms. Slow plate. " A " eyepiece. Sixteen minute*. 

 Ditto. Ditto. No eyepiece. Ten minutes. 



Aspartic Acid. No eyepiece, 

 minutes. 



Chromatic plate. Eight 



