

INDEX, 



453 



"Kirchhoflf (continued] 



- of general light of sun, 109 



intensities of Fraunhofer lines, 



173 



researches on spectrum of iron, 74 

 results on solar elements, 76, 93 

 statement as to the identity of 

 solar and terrestrial spectra, 156 

 statement on the variations of in- 

 tensities of lines by temperature, 

 178 



theory of sun, modified by Frank- 

 land and Lockyer, 165 



L. 



Latitudes of sun-spots, 430, 436, 438, 



444 



Layer, reversing, 303 

 Layers in solar atmosphere, 169, 402 

 Lamp, electric, description of, 84 

 Lavoisier, views on elements, 59 

 Lead, in sun, 158 

 Lens, collimating, first used, 26 



use of, for spectroscopic work, 25, 



140, 142 

 Light, absorption of, first noticed, 



Herschel, 37 

 analogous to sound, 87 

 determination of wave-length of, 



86 



experiments on lighthouses, Glad- 

 stone, 65 



Fizeau's researches on, 1 35 

 Fraunhofer 's, 20 

 nature of, 2 



produced by electricity, investiga- 

 tion of, 21 



researches on, Kirchhoff, 54 

 velocity of, 87 

 Line slit, why used, 32 



solar, new test for reversal of, 156 

 spectrum, experimem on produc- 

 tion of, 240 



Lines, absorption, trumpeting of, 381 

 absorption, in arc non-symmetrical, 



381 



absorption, observation on, Frank- 

 land, 378 



basic, Thalen's statement on, 371 

 bright in naked arc, 383 

 bright in solar spectrum, 171 

 calcium, in spots and prominences, 



376 

 coincident, in different spectra. 



232 

 coincident, due to impurities, 154 



Lines (continued} 



common to many spectra, 177 

 common to two substances, 376 

 compound, origin of, 301 

 contortion of, in spectrum, 119, 



120, 132 



contorted in sun-spots, 348 

 Fraunhofer's intensities of, Kirch- 



hoff's paper on, 173 

 Fraunhofer's intensities of, varia 



tions of, 174 

 inversion of, 314 

 in electric arc, origin of phenomena 



of, 379 



in prominences, Tacchini, 344 

 iron, change of refrangibility of, 347 

 iron, frequencj' of, in sun-spots, 



328, 340 



iron, in spectrum of arc, 333 

 iron, in spectrum of chromosphere, 



335 

 iron most widened in sun-spots, 



320 

 long and short, description of, 



144, 145 

 nickel, in spots and prominences, 



375 

 nickel, most widened in sun-spots, 



321 



of chemical elements, 331 

 physical pecularities, 221 

 reversal of, phenomena of, 223 

 seen during volatilization, 294 

 short, behaviour of, 291 

 in spectrum of Sirius, prediction 



about, 250 



in spectrum of sun-spots, discus- 

 sion on, 255 ; spectra of two 



or more substances, 252 ; 



spots most widened, table of, 



317 

 in spots and prominences, result of 



observations of, 257, 374 

 titafrium, most widened in sun- 

 spots, 321 

 ultra violet, discovered by Bee- 



querel, 48 

 unknown, widened in sun-spots, 



322 

 visible in spots and prominences, 



328 

 Lithium, 294 



effect of temperature on spectrum 



of, 241 

 Frankland's letter on spectrum of, 



242 

 spectrum of, variations of intensity 



in lines of, 197 



