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, 28*5-287 



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-polar iscope, 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 



