19S 



Moellers Test Plate, 132 



Monocular Microscope, 61 



Movable Object Carrier, 56 



NEGATIVE EYEPIECE, u 4 



Nose-piece, ... 46, 59 



Numerical Aperture, 87 



Numerical Aperture, How to Measure, 89 



OBJECT, 49 



Object Carrier, Movable, 56 



Object, Opaque, 137 



Object, Resolution of, 92 



Object, to Find, 122 



Object, to Illuminate, 124 



Object, to Measure, 170 



Object, When Centered, 49 



Objects, How to Draw, 163 



Objects, Test, 132 



Objects, Test, Which to Use, . . 131 



Objectives 46, 72, 77, 85, 86, 138, 147, 182, 183, 184 



Objectives, Adjustable, 98, 144 



Objectives, Angle of, Si 



Objectives, Apochromatic, 112 



Objectives, Care of, , 190 



Objectives, Classification of, 79 



Objectives, Powers of, 79 



Objectives, Rating of, 78 



Obje .tives, Systems of, 79 



Objectives, Testing of, 95, 96, 149 



Objectives, to Attach, 121 



Objectives, Tube Length of, 78 



Oblique Illumination, 161 



Ocular, 46, 72, 112, 114, 182, 183 



' Oculars, Care of, 190 



Oculars, Rating of, 117 



Oil Immersion Objectives, 77, 78, 85, 86, 147 



Opaque Object 137 



