446 



OPTICAL PROJECTION 



MEN 



Mending gas-bags, 42 



Mica designs, for polarised light, 

 354, 307, 374, 381 



Microscope, attachment, 148 ; pro- 

 jecting and electric, 179 ; com- 

 pound, 190 ; objectives for, 192 



Microscopic bi-unial, 157 



Microscopic demonstration image, 

 the, 190 



Mineral oil lamps, 36 



Minerals, sections of, 359 



Minimum deviation in prisms, 283 



Mirror, plane, 175 ; rotating, 269, 

 400 



Mitscherlich's experiment with 

 selenite, 379 



Mixed gas jets, 51, 59 ; best form 

 of, 62, 63 



Mixing gases, danger of, 51, 53, 90 



Mixture for oxygen, 77 



Mohture, condensed, 16, 116, 206 



Molecular motion and heat, 389; 

 strains, 229, 360 



Monochromatic lights or colours, 

 303 



Morton, Prof., on thallene, 319 ; 

 his vertical apparatus, 166 



Mounting experimental lanterns, 

 175 ; diagrams, 415 ; polarising 

 slides, 357 



Mounts for objectives, 32 



Movements, physiological, 232 



Muscle-telegraph, 238 



Muybridge's moving figures, 145 



NERNST lamp, 41, 424 



Newton's experiments in refraction 

 of colours, 283 ; disc, 288 ; rings, 

 328, 354 ; orders of colours, 356 



Newton's, Messrs., triple experi- 

 mental lantern, 160, vertical do., 

 169 



Nicol prisms, 339 ; improved, 340 



Nipples, 62, 65 ; inclination of, 67 



Nodes, 252, 267 



Norremberg's artificial crystals and 

 mica-selenites, 382 



Npzzles for gas-supply, 4J 



PHO 



OAKLEY'S cut-off jet, 118 

 Objectives for lanterns, 24; size 



and cost of, 31 ; testing ; 32, of 



microscopes, 192 

 Objects for microscope, 202; living, 



204 



Oersted's experiment, 403 

 Oil-lamps, 34, 417 

 Opaque objects, 147 

 Opeidoscope, Dolbear's, 268 

 Opera-glasses in microscopic 



demonstration, 191, 199, 208 

 Optical lantern front, 171 

 Organic substances, in polarised 



light, 359 

 Oscillation in electrical discharge, 



400 



Osmosis in gas-bags, 43 

 Oxide, thin films of, 324 

 Oxy-carbon light, 100 

 Oxy-ether light, 91 

 Oxygen, preparation of, 74, 80 ; 



price of, 88, weight of, 85 

 Oxy-hydrogen microscope, 182 ; 



management of, 196 



PACKING of jets, 60, 63, 93 

 Packing the lantern, 135 

 Painted slides, 136 

 Panoramic slides, 141 

 Pantagraph lantern-sketcher, 145 

 Parallel beams and pencils, 172, 



257, 276 



Parallelogram of forces, 217 

 Particles, polarisation by small, 



382 



Pearl, mother of, 336 

 Pencils of rays, management, 172, 



257, 276 ; attachment to lantern 



for, 173 



Perforated plates, diffraction by,337 

 Persistence of vision, 144, 288, 371 

 Petroleum ether, 96 

 Petroleum oil lamps, 36, 417 

 Petzval objectives, 28, 192 

 Pfaundler, Prof., and apparatus for 



Lissajous' figures, 259, 26Q 

 Phoneidoscope, the, 270 

 Phosphorescence, 32Q 



