( 589 ) 



nol iTprcsciil llic (v\|t('riiii('iilal dala willi pcrrcct acciiracN'. Koi- tlic 

 c-on-ecli()ii, inli'odiiccMl hefoiv lor llic paiMial coiiicidciicc of llic (lislaiicc 

 spluM-os lias nol hccii laken inio accoiinl in llio (Icdnctioii of iliis 

 forninla. 'V\w ((nanlilv /> 'm r h lor a nionaloniic nas, v. u. 

 mei-cnrv \aponi', ar.u'on clc. wdnid accordinu- lo llic new tli(>(,|-\- of vw 

 DKK Waaj.s remain inxariahlc ; w heisas Iliis (piaiilit\ w liidi accordinii' 

 lo llie fornicM' consiiioralions \vonld loi- wvy lariic xolnnics hc ('(pial 

 to fonr linios llie niokmlai' xoliinir. lor smaller \-oliinies would 

 certainlv lia\(' a smallci' \alue, and il \vonld a|)proa(di lo ahonl twice 

 llie molcculai- volume — at least if the slia|>e of llie molecules does 

 nol exeix'ise am' iniluence on this calculation. 



Physics. — •' /*('('/i/i(n'/firs r/ii(h-/i(/ii(/i'S(>f Frtdiiilio/cr Iiih'.s Infi'i-inrtcd 

 ((,s coDscqifenct'.s' of anomalous dlsju-rslon of .sfmJ((/ht in, the 

 corona" by Prof. W. H. Julius. 



(Communicated in the meeting of February :2s, 1903). 



Especially by Jkwkll's investigations on the coincidence of solar 

 and metallic lines ^) attention lias been drawn to several \ariable 

 peculiarities of Franidiofer lines. Here we do not mean the irregu- 

 larities occurring in the spectrum of spots or of faculae, a\ liich relate 

 to disturbances in comparatively small ])arts of the sun, but abnor- 

 malities shown by the avei-age sujdight, as observed when the slit 

 is illuminated by a long strip of an imperfectly focused solar image. 

 In that case, according to Doppler's principle we may, of course, 

 expect displacements of the lines in consequence of the Sun's rotation, 

 of the rotation of tlie Eai'th, and of the change in the distance between 

 Sun and Earth caused by the excentricity of the Earth's orbit. Hut 

 even when all these influences have been allowed foi-, some irre- 

 gularities still remain. 



Indeed, Jkwklf. has observed that some Fraunhofer lines do, others 

 do not, exactly coincide with the emission lines in the ai'c spectrum 

 of elemejits, ami that the displacements are imequal both for lines 

 of diflferent elements and for the various lines of one and the same 

 element. Moreover, the shifting of certain lines on one set of [)hoto- 

 graphic plates was sometimes found diilerent from that on a set of 



^) L. E. -Jkwicll, "The coincidence ot solar and metallic lines. A study of the 

 appearance of lines in the spectra of tlic electric arc and the Sim." Asfropli. 

 Journ. Ill p. 89 — 11:3, l89(j. The same : "Spectroscopic notes. Absolute wave-lengths, 

 spectroscopic determinations of motions in the line of sight, and oilun' related 

 subjects." Astroph. Journ. XI p. 234—240, 1900. 



