INDEX 



463 



Non-adjustable objectives, 77 



thickness of cover-glasses for, 286- 

 287 

 Normal liquid, 363 



salt or saline solution, 363 

 Nose-piece, revolving, 28-29 

 Numerical aperture and table, 294-297 



O 



Object, determination of form, in 



image, relative size of, 138-139 



micrometer, 135 



mounting, 321 



printing image of direct, 234 



suitable for photo-micrography, 223 

 Objective, 19 



achromatic, 21, 291, 436 



adjustable, 22, 157, 285-287 



adjustment, 77, 157, 229 



aerial image, 31, 33 



aperture, 294, 297 



aplanatic, 21 



apochromatic, 22, 291, 437 



back combination of, 21 



cleaning, 92-93 



cloudiness or dust on, 34 



collar, graduated, 79 



designation or nomenclature, 19-23 



dry, 21 



equivalent focus of, 19, 27 



field of, 29 



focusing for micro-spectroscope, 258 



front combination, 21 



function of in the microscope, 31-32 



homogeneous immersion and clean- 

 ing, 21, 82 

 experiments with, 81-82 



immersion, 21 



initial magnification, 19, 305 



inverted, real image by, 34 



low and high, 20-23 



magnification of, 19, 131, 305 



micro-polariscope, 267 



microscopic, 19—23 



micro-spectroscope, 257 



names of parts, 21 



nomenclature or designation of , 19- 

 23 



non-adjustable, unadjustable, 22, 

 157, 285-287 



nose-piece for, 28-29 



numbering or lettering, 19 



numerical aperture, 294-297 



oil immersion, 21, 295, 438 



pantochromatic, 22 



para-chromatic, 22 



parfocal, 38-39 



photo-micrographic, 220-222 



projection, 201 



screw-thread for, 103-106 



semi-apochromatic, 22 



table of field, 29-30 



terminology or designation, 19-23 



unadjustable, non-adjustable, 22, 

 . 157, 285-287 



variable, 22 



visual and actinic foci in, 222 



water immersion, 21, 80 



working distance, 39-40 

 Oblique light, 47, 65-67 

 Oculars, various forms of, 23 



cloudiness or dust on, 93, 109 



comparison and fig., 123 



compensation, 24, 26, 292-293 



concave or amplifier, 429-434 



designation or nomenclature of, 

 23-26 



equivalent focus, 27 



eye-point of, 15-33 



field-lens, 25, 308-309 



filar or screw micrometer, 147-149 



for two observers, 433 



function of, 32 



Huygenian (fig.), 6, 25-26, 146-147 



indicator or pointer, 102, 195 



lettering and numbering, 26 



magnification of, 27, 308-309 



micrometer and micrometry, 143- 



153 

 negative, 23 

 parfocal, 38, 309 



photo-micrography, 220-222, 231 

 pointer or indicator, 102, 195 

 positive, 23 



power or magnification of, 26-27 

 projection, 201, 226 



