INDEX 



817 



ILFOED orthochroraatio plates, 220 

 Illuminants, kinds of, 75 ; position 

 of, 162, 164; vide Acetylene, 

 Arc-light, Lime-light, Oil, Sunlight, 

 Welsbach gas ; heat from, 180 ; 

 of high-intensity, danger to eyes 

 from, 1 4 ; difficulty from small 

 area, 107, means of overcoming, 

 107, 108 ; for coloured lantern- 

 slide making, 278, 280 

 Illumination, importance of, 69, 75 ; 

 vide Annular, Bacteria, Dark- 

 ground, Metal Surfaces, Oblique, 

 Opaque objects ; of dark-room, 

 198-200 



Immersion fluids, oil, 19 ; mono- 

 bromide of naphthaline, 19 ; how 

 to apply, 24, 150 

 Immersion lenses, vide Objectives, 



immersion 

 Imperial orthochromatic plates, 284, 



288, 296, 299, 301-303 

 Incandescent gas, vide Welsbach gas 

 India-rubber supports for camera, 176 

 Instantaneous photos, 139, 141, 295 

 Intensification, 235, 298 ; in lantern- 

 slide making, 248, 249 

 Internal reflection, 152, 179, 287 

 Iris-diaphragm behind low- power 

 objective, 22, 286 ; for use with 

 collecting-lenses, 71, 73, 149, 170- 

 174, 181 ; under sub-stage con- 

 denser, 8, 49, use of, 148, 161 ; 

 between microscope and light, 181 ; 

 with vertical illuminator, 262 

 Isochromatic plates, 200, 219, 220, 287 

 Isolar plates, 220, 221 



KTNGSFORD'S trough, 209 

 Koch's spirillum of cholera, 297 

 Kohler, Dr., collecting-lens system, 



71, 170-172, 181 ; ultra-violet 



light apparatus, 250-255 



LAMPS, vide Arc, Mercury-vapour, 

 Oil ; for dark-room, 198-200 



Lantern-slides, dry-plate, 232, 242- 

 245 ; wet-collodion, 219, 245- 

 248 ; illumination of dark- 

 room, 199 ; projection of, 249 

 in colour, uses of, 276 ; Sanger 

 Shepherd, three-colour method, 

 277-279 ; Lumiere auto- 

 chrome, Thames and Dufay 

 colour-plate processes, 277, 

 280 -282 ; development of 

 negative, 278 



Latherby, A., 224 

 Laws, E. F., on Alloys, 265 

 Leitz, E., arc lamps, automatic, 103, 

 hand-feed, 106, 165 ; camera, 

 vertical, 114, combined vertical 

 and horizontal, 115 ; dark-ground 

 condenser, 59 ; microscope stand, 

 14 ; micro-metallograph, 142 ; 

 stops to reduce aperture of objec- 

 tive, 22 ; vertical illuminator, 67, 

 in micro-metallograph, 144 

 Length of camera, vide Camera 

 Length of exposure, vide Exposure 

 Lenses, vide Objectives 

 Lepidocyrtus curvicollis, 158, 300, 



301 



Leprosy, bacillus of, 299 

 Leybold's cementing process, 208 

 Lieberkuhn reflector, 65 

 Light-excluders, 178 

 Light- filters, vide Colour-screens 

 Lime-light, actinic value of, 81, 226 ; 

 its production from coal-eras, 

 81, from house-gas, 82, from 

 ether or gasoline, 81, 82, 84 

 mixed jet, 81-83, limes for, 84> 



types of, 87, Gwyer, 87 

 blow-through, 82, 84, 86, limes 

 for, 85 ; Saturator method, 84, 

 Pendant (Will way & Sons), 

 84; Zirconium discs (Zeiss), 

 85 



cylinders for, 85 ; regulator 

 (Beard), 86; Pringle's cut- 

 off tap, 87 ; stands for, 87 ; 

 use of, 168, 169; heat from, 

 180 



Limes, selection of, 84, 85 

 Limit of visibility, 26, 60 

 Liquid-cells for dark-room, 199, 200 ; 



for colour-screens, 208, 209 

 Lister Institute of Preventive Medi- 

 cine, 130, 175 

 Low-power objectives, 19, 284 ; tests 



for, 28, 285 



Low-power work, 24, 286 ; collecting- 

 lens system for, 70, 73, focussing 

 in, 150; light for, 76; with 

 ground-glass screen as illuminant, 

 169 ; stereoscopic, 274 

 Lumiere plates, 220 ; autochrome 

 for coloured lantern-slides, 277, 

 280-282 



' Luna, ' Nernst lamp, 90 

 Lung, B. tuberculosis in, 296 



MACROPHOTOGRA.PHY, 138 

 Magnesium light, 75 



