200 



Slips, Glass, 49 



Slow Motion, 65 



Society Screw, 46 



Solid Eyepiece, 115 



Spectrum, 24 



Spectrum, Secondary, 94, 112 



Spherical Aberration, 22, 96, 140 



Spring Clips, 48 



Stage 47, 53, 180 



Stage, Glass, 56, 181 



Stage, Micrometer, 170 



Stage, Revolving, 55, 182 



Stage, Space Below, , 1 80 



Stand, 43, 176 



Striae, 119 



Substage, 48, 182 



Substage Bar, 48 



Substage Condenser, 154, 182 



TESTING OBJECTIVES, 95, 96, 149 



Test Objects, 132 



Test Objects, Which to Use 132 



Test Plate, 132 



Triple Nose-piece, . . . 60 



Triplet, Hastings, .... 30, 38 



Triplet Lens, 30, 38 



Tripod Magnifier, 32 



Triplet System, ._ 80 



Tube Length, 50, 78, 176 



UNDER-CORRECTION, 95 



Universal Screw, 46 



VIRTUAL FOCUS, 20 



Virtual Image, 22 



WOLLASTON CAMERA LUCIDA, 164 



Water Immersion Objective, 85, 86 



Working Distance, 106 



Working Distance, to Measure, 107 



