INDEX. 



ABBE'S method of determining Angle of 



Aperture, 176. 



,, process for testing, 157, 160. 

 ,, theorem of Inclination of Rays, 25 

 Abbe, E., on Angle of Aperture, 95. 



,, on Illuminating Apparatus, 111. 

 Aberration, Chromatic, 50-53. 



,, ,, testing the, 158- 



167. 



,, ,, of air- bubbles in 



water, 201-202. 

 ,, Spherical, 53-65. 



,, ,, testing the, 149- 



158. 

 ,, ,, in the Eye-piece, 



62. 



Abies excelsd, D.C., example of polarisa- 

 tion, 370. 



Achromatism only approximate, 53. 

 ,, and aplanatism, 53-56. 



See "Eye-piece," "Lenses." 

 Adjustment, Plane of, Interferences in, 



240-247. 



Air, as medium for dry substances, 281. 

 ,, in prepared sections, how remedied, 



279. 



Air-bubbles in water, 191-202. 

 Algse, study of Division in lower, 280. 

 Amylodextrwie, crystals of, example of po- 

 larisation, 372-373. 

 Analyser, the, 311-315. 

 Angle of Aperture, determination of, 172- 



177. 



,, ,, effect of Illuminating 



Apparatus upon, 103- 

 111. 



,, ,, importance of, 93-97. 



,, ,, relation between Focal 



Length and, 99-101. 

 Aperture, Angle of, see Angle. 



,, of Lenses, diffractional action 



of, 102-103. 

 Aplanatism, 53-56, 64, 65. 



See "Eye-piece," "Lenses." 



Base, the (microscope-stand), 120. 

 Beneche, No. 9 objective, determination 



of cardinal points of, 186. 

 Binocular Microscopes, 48-50. 



stereoscopic, 222-226. 

 Bodies. See ' Liquid, " and " Solid. " 

 Brightness of Field, 84-90. 



,, in simple Microscope, 259. 

 Browning's Spectral Eye-piece, 47-48. 

 Bubbles, Air-, in water, 191-202. 



CAMERA LUCIDA, for drawing, 298. 

 Campani (" Huyghenian ") Eye-piece, 



35-42. 



Canada balsam, preserving medium, 281. 

 refractive Index of, 305- 



307. 

 Cardinal points, Optical, 9. 



,, determination of, 23, 



184-188. 

 Caulerpa prolifera Lamowx, example of 



polarisation, 370. 



Cedrus libanotica Lk. , example of polarisa- 

 tion, 371. 



Cell, Culture-, 280. 

 Cells, gutta-percha, india-rubber, and 



glass, 285-287. 

 ,, wood, examples of polarisation, 



379. 



Cements for sealing, 286. 

 Centering of systems of lenses, 79-84. 



testing the, 170-171. 

 Chaincedoris annulata Mont., example o 



polarisation, 370. 

 Chevalier's lenses, 263, 264. 

 Chloride of calcium, preserving medium, 



282. 



Chromatic Aberration, 50-53 ; 158-167. 

 Coddington's lenses, 262. 

 Colours, Interference, of thin plates, 



245-247. 



Cover-glass, employment of, 271-272. 

 ,, influence of, 65-68. 



