454 



INDEX. 



Limb, selective absorption at, Vogel, 



104 

 Liveing and Dewar, experiments on 



shielded arc, 393 et seq. ; work of, 



393 ; views on spectra quoted, 401 

 Lorenzoni's addition to lines in 



spectra of prominences, 184 



M. 



Maclear's, Capt., observations during 



eclipse of 1871, 166 

 Magnesium, effect of temperature on 



spectrum of, 241 

 experiments on, Frankland, 148 

 spectrum of, 149 

 variations of intensity in lines of, 



196 



Manganese, spectrum of, 380 

 Mascart's reason for employing dif- 

 fraction, 86 



Matter, composition of, 260 

 Maxwell, Clerk-, definition of an 



atom, 400 



on the decomposability of ter- 

 restrial elements, 267 

 Measurement, Kirchhoft's method, 



172 



Metalloids, spectra of, Salet, 193 

 Metals in sun, discovery of, 219 ; lists 

 of, 158, 220 ; table of variations 

 of intensities, 231 

 in sun-spots, 256, 314 

 investigation of, Hofmann, 79 

 mechanically mixed, spectrum of, 



151 



Meteorites, solar, 438 

 Miller's remarks on his photograph of 



electric spectra, 147 

 spectra of stars, 173 : Aldebran, 



187 

 Mitscherlich's conclusion on spectra 



of compounds, 159 

 multiple spectra, 190 

 observation on fluted spectra, 179 

 Mixture, spectrum of a, 151 

 Motion, forms, 123 



indications of, by different lines, 



175 



Molecules, groups of, simplified by 

 temperature, explanation of, 

 261 



increase of complexity of, illustra- 

 tion of the, 263 

 mixtures of, 389 



Molecular simplification, Schuster 

 quoted, 288 



N. 



Newall's refracting telespectroscope, 



98 

 Newcomb's observations in 1878, 



438 



Newton, Sir I., 5 

 quoted, 367 



experiments with prism, 6 

 Prof., conclusion as regards the 



corona, 367 



Nickel, lines most widened in sun- 

 spots, 321, 375 



present in solar atmosphere, 77, 80 

 Nitrogen, spectrum of, method of 



observing, 153 



Nitrous acid gas in sun, according to 

 Brewster, 43 



o. 



Oxygen, spectrum of, method of ob- 

 serving, 153 

 Schuster's observations, 285 



P. 



Period, synodic, 425 



Perry's solar observations, 406, 407, 



433 

 Peters' s solar observations, 406 



spot observations, 410 

 Photograph of arc phenomena, 386, 

 387 



of equatorial extension, 438 



of eclipses. (See Eclipses.) 



of naked arc, 383 



spectra, results of, 217 ; Abney's, 

 211 



of spectrum of flame of arc, 381 



of sun, best method of obtaining, 



211 



Photography, use of, 209 

 Photosphere, condition of, 166 



nature of, 166 



Planets, same spectra as sun, 22 

 Plato, 4 

 Plucker's multiple spectra, 190 



observations on fluted spectra, 179 

 Poles, currents from, 432, 436 

 Pores, 408, 418 

 Polymerism, 270 

 Potassium, 294 



lines of, 299 



spectra of, in tubes, 300 



vapour of, Roscoe, 277 



