822 



INDEX 



Tube-length, 7 ; English and Con- 

 tinental, 40, 151, 195 ; adjustment 

 to objective, 150, or objective- 

 changer, 36, 151 ; to correct for 

 thickness of cover-glass, 155, 157- 

 160 



UNDER-EXPOSURE, 233-235 

 Ultramicroscopic method, 59 

 Ultra-violet light, 250 ; resolving 

 power in relation to wave-length, 

 250 ; monochromat, 251 ; Zeiss- 

 Kohler apparatus for, 27, 250-253 ; 

 how to use, 251-255 ; precautions 

 with, 152 ; magnification by, 252 ; 

 focussing with, 254 ; plates for, 

 222, 255 ; preparation of speci- 

 mens, 252 

 Uranium intensification, 235, 236 



VAN HEURCK, microscope stand, 1 1 ; 

 camera, vertical, 117, 140, 295; 

 'The Microscope.' 311 



Ventilation of dark-room, 202 



Vernier, 7 



Vertical illuminators and illumination, 

 61 ; vide Metal surfaces and 

 Opaque objects 



Vibration, 112, 175, 178; as depend- 

 ing on position of room, 175, 176, 

 on foundations, 175 ; prevention 

 by india-rubber supports, 176, by 

 springs, 177, by floating, 178; 

 when exposing, 189 



Violet light, 214, 222 ; resolution by, 

 216 



Voltmeter, 105 



Von Rohr, Dr., 27 



WALES microscope, 9 

 Warnerke sensitometer, 222 

 Water- bath to absorb heat, 180 ; 

 to stop reflection in bacteriological 

 work, 24, 268 



Water-supply of dark-room, 201 

 Water-vapour, to remove from bac- 

 teria tube, 272 



Watkins, exposure-meter, 225 

 Watson, W. & Sons, camera, hori- 

 zontal, 122, combined vertical and 

 horizontal, 116, vertical, 117, 140; 

 heliostat, 108 ; holoscopic ocular, 

 42; Kingsford's trough, 209; 

 microscope stand, Van Heurck, 11, 

 Royal, 14 ; objective-changer, 



38 ; sub-stage condensers, 53 ; 

 vertical illuminator, 66 



Watson-Gonrady, collecting-lens sys- 

 tem, 70, 169 



Wave-length, 200, 212, 213, 216, 302 ; 

 ultra-violet, 250-252 



Wellington orthochromatic plates, 

 220/285, 289 et a&j. 



Welsbach gas, 77 ; collecting-lenses 

 for, 74 ; with Zeiss paraboloidal 

 condensers, 58 



Wet-collodion plates, 218; for lantern- 

 slides, 245 



Will way & Sons, Pendant saturator, 

 84 



Wratten and Wainwright's green 

 colour-screens, 199 ; monochro- 

 matic filters, 217 ; plates for 

 lantern-slides, 242, 290, 301, Allo- 

 chrome, 288, Panchromatic, 220 ; 

 speed-value of plates, 227 



Wynne exposure- meter, 225 



YEAST CELLS, unstained living, 295 



ZEISS, CARL, Abbe apertometer, 307 ; 

 arc lamp, 103 ; camera, photo- 

 micrographic, 126, 141, combined 

 vertical and horizontal, 137, hori- 

 zontal, 126, vertical, 114; collect- 

 ing-lens system (Kohler), 71, how 

 to use, 170-172, 181 ; condensers, 

 60, stop for, 55, paraboloidal, 57, 

 centreing-collar for objective used 

 as condenser, 50 ; control of fine 

 adjustment, 128, 132, 190; filter 

 blue-glass, 213 ; liquid cells, 208 ; 

 microscope stand, 11, for metal- 

 lurgical work, 256, Martens' model, 

 259 ; objectives, apochromatic, 26, 

 30, 33, monochromatic, 27, 251, 

 253, of high aperture, 19, Planar, 

 276, Prolar, 273 ; oculars, com- 

 pensating, 38, 40, projection, 44, 

 tape measure for use with, 45 ; 

 sliding objective-changer, 36, 151, 

 163 ; spherical flask, as collecting- 

 lens, 58 ; stops to reduce aperture 

 of objective, 22 ; ultra-violet light 

 apparatus, 250-255 ; vertical illu- 

 minator, 66 ; zirconium discs, 85 



Zettnow's colour-filter, 212, 294, 

 300 



Zirconium discs (Zeiss), 85 



Zylol, 255 



Svottiswoode & Co. Ltd., Printers, Colchester, London and Eton. 



