312 



THE USE OF THE MICROSCOPE 



Objectives, marking, 128 

 measuring aperture, 267 



magnification, 152, 264 

 metallurgical, 157 

 monobromide of naphthalin, 104, 

 202, 207 

 use of, 266 

 monochromatic, 202 

 oil-immersion, 34 

 correcting, 113 

 origin, 199 

 of optimum quality, 262 

 overcorrection of, 121 

 parfocal, 40, 140 

 practical points, 129 

 structure of, 116 

 suggested monochromatic, 206 



photographic, 206 

 summary, 128 

 testing, 155, 172 

 tests for correction, 122 

 for uncovered objects, 265 

 with uncovered objects, 263 

 undercorrection of, 121 

 used without cover-glasses, 33 

 water and oil-immersion com- 

 pared, 268 

 water-immersion, 3, 34, 131 

 advantages of, 131 

 correction collar, 132 

 history, 198 

 kinds of, 132 

 practical points, 135 

 precautions with, 133 

 summary, 134 

 test object for, 134 

 Oenothera, chromosomes, 227 

 Oil, immersion, appropriate, 260 



objects in, 255 

 Optical rules disregarded with micro- 

 scope, 4, 5 

 regarded, with microscope, 4, 5 

 Orthomorphy, 43 

 Outfits, microscope, 154 

 Over-correction of condenser, 89 

 of objective, 121 



Pachytene, chromomeres at, 219 

 Paraffin oil, as mounting medium, 

 103 



useless for immersion, 103 

 Paramcccium, in cultures, 240 

 Petri dish, plate-glass cover for, 10(5 

 Phagocytosis, 240 

 Phoku camera, 143, 166 



care of, 183 



testing, 173 

 Photographic prints, over- 



developed, 167 

 Photographs, enlarging, 167 

 Photography, 165 



apparatus, 170 



with camera lens over evepiece, 

 166 



errors in, 165 



exposure, 167 



future of, 207 



objective 120 for, 124 



optimum methods, 166 



practical points, 170 



practice in, 168 



with short waves, 168 



stains for, 167 



ultra-violet, 168 



Wratten book on, 77 

 Polar granules, 221 

 Pollen-grains, nuclei, 228 

 Preparations, microscopical, 104 



care of, 178 

 Prism, double, 41 



reflecting, 33, 137 

 care of, 176 



for total reflection, 248 

 Prisms, Greenough reflecting, 43 



Porro, 23 



rhombohedral, 22 



Questions, 269 



Q 



R 



Rackwork, care of, 181 



Realgar as mo\mting medium, 104 



