Object, What to use as, 132 



Objective, . 31, 55, 60, 99, 189, 190 



Adjustable, ' 64, 143 



Angular Aperture of, 70 



Apochromatic, 102 



Care of, 69, 200, 201 



Caution in Choosing, 190 



Color Correction in, 86 



Construction of, 67 



Defects in, 112 



How to Focus, 124 



How to Attach, 117 



Immersion, 60, 75, 146 



Illuminating, 64 



Influence of Cover Glass on, 93 



Photographic Microscope, 64 



Powers of, 62, 99 



Projection, 65 



Quality of, 70 



Rating of, 62 



Searcher, 126 



Special, 64 



Systems of, 65 



Variable, 64, 143 



Wide Aperture, 190 



Oblique Light with Condenser, 164 



Ocular, 31, 55, 104, 200 



Oil Immersion Objectives, 60, 75, 99, 146 



Opaque Objects, 151 



Open Adjustment, 143, 145 



Opening or Aperture, . 73 



Optical Axis, 34 



Optical Glass, 57, 67 



Optical Properties of Lenses, 1 



Orthoscopic Eyepiece, 109 



Over-Correction of Objectives, 86 



