4S6 



INDEX 



Cutting sections, free-hand, paraflSn, 



collodion, 374-375, 387 

 Cyco photographic paper, 178 

 Cylindrical spectacles, 427-428 



D 



Dark-ground condenser or illuminator, 



71-73 



iUuminationj 67-76, 120, 297 

 Dark room for drawing and photog- 

 raphy, 217, 242 

 Daylight, 45 



artificial with curve, 49-53, 203-205 



glass, 50-53 



lantern with, 203-205 



table with, 203-205 

 Decalcifier, 354 

 Dehydration, 395 

 Demonstration, class, 193-205 



lantern and table, 203-205 



projection microscope, 197-203 

 Denatured alcohol, 349 

 Deparafiining, 384 

 Designation of oculars, 23-26 



of wave lengths of light, 256 

 Determination of field, 29-30 



magnification, 136, 307 



working distance, 41 

 Developing and light for, 241-242, 243 

 Diamond for writing, 401 

 Diaphragms and their use, 47, 48, 62, 



181 

 Diatomes, 335-336 

 Dichromate cleaning mixture, 320 

 Diffraction of light, 280, 300-302 

 Diffuser, ground-glass for, 50-53, 181 

 Diffusion currents, avoidance, 396 

 Direct light, 45 



vision spectroscope, 249 

 Disc, Ramsden's, 34 

 Dispersion of light, 280 

 Dissecting microscope, 88-90 



spectacles, 87 

 Dissociating liquids, 354 

 Dissociator, 332, 354 



Formaldehyde, 354 



Miiller's fluid, 354 



nitric acid, 354 



Distance, standard for microscopy, 139 



working, 39-40 

 Distinct vision, near point, for adults, 



130 

 Distinctness of outline, 114 

 Distortion in drawing, 162 

 Diverging lens, 281 

 Dividers, measuring spread of, 134 

 Double-objective binocular, 83-88 



ocular, 433 

 Double vision, 134 

 Doubly contoured, 116 



refracting, 268 

 Draw-tube, 27, 37 

 Drawing, 160-193 



board for camera lucida, 166, 169 



camera lucida, 161-170 



distortion, avoidance of, 162 



erect images in, 172-176 



free-hand, 161 



inversion in, 172-176 



magnification of, 309 



microscopic, 162-174 



models, 416-420 



photographic camera for, 161, 173, 

 176-178 



projection apparatus for, 161, 183- 

 188 



room for, 242 



scale and enlargement, 170-172 



table and shelf for and fig., 179, 186 



with low and high powers, 186, 187 



with the simple microscope, 188, 

 190 

 Drawings, lettering, 190-191 



on back of photographic prints, 178 



on bUie prints, 178 



on a vertical or horizontal drawing 

 board, 185 



reduction for publication, 190 

 Dry mounting, 323 



objectives, and aperture, 21, 296- 

 297 



plates, 244 

 Drying rack for bottles (fig.), 366 

 Dust of living rooms, examination, 123- 

 124^ 



on objectives and oculars, 34, 109 



