r>6 



PROF. COPELAND AND DR L. BECKER ON THE 



It is noteworthy that some of the brightest lines given above were observed by me at 

 Dunecht in the spectra of R Andromedse and R Cygni on October 28, 1889, on an intima- 

 tion by the Rev. T. E. Espin that the inline appeared bright in the spectra of these stars. 

 Although the observations of these stars could not be completed on account of my remov- 

 ing to Edinburgh shortly afterwards, I give the wave-lengths of all the brighter lines in 

 their spectra, all of which, it will be seen, agree closely with prominent lines in the spec- 

 trum of the Nova. R Andromedse was observed with the slit rather open. 



R Andromedse. 



R 



Cygni. 



Nova Aurigae. 



\ Intensity. 



A 





Intensity. 



A 



Intensity 



... ... 



532-3 





4 



533-0 



4 



528-6 3 



528-9 





3 



528-0 



3 



517-1* 4 



517-0 





4 



517-4 



5 



494-5 4 



...f 







493-2 



5 



486-7 6 



486-0 





6 



486-9 



6 



Postscript added lUh March 1892. 



The new star still continuing bright enough to be observed with the spectroscope, 

 I returned to Dunecht on February 24, but was very unfortunate with the weather. 

 On March 4 I found that the intensity of the spectrum had much decreased, but that the 

 bright lines were still easily seen. From C to 550 I again measured all the brighter lines, 

 while between 550 and FI obtained almost every line that is given above. Thirty-eight 

 lines in all were re-measured, but the results are not combined with those already given. 

 Beyond F the light was too faint for measuring. The results agree with the earlier ones 

 as closely as the size of the spectroscope entitles one to expect. The power 14 was 

 employed. The intensity of some of the lines relatively to each other appeared to be 

 changed. Certainly F was no longer the brightest line, the line 5 17 '5 considerably sur- 

 passing any of the others. I was not able to detect any narrow dark lines which had been 

 announced in the meantime, but I measured the middle of the dark spaces to the violet 

 of some of the brightest lines, which formerly I had attributed to the effect of contrast. 

 The wave-lengths of the brightest lines in the green-blue, and their relative intensities 

 (the brightness in February is given in parentheses), were observed as follows : — 



Number of 









Observations. 



X 



Intensity. 



Remarks. 



2 



533-4 



4 (4) 





2 



528-7 



4 (3) 





2 



524-6 



4 (2) 





2 



517-5 



6 (5) 





2 



502-7 



5 (5) 



Breadth, 0"5. 



1 



501-2 





Middle of dark space ; breadth, 2'0. 



3 



493-0 



4 (5) 



Dark bands to the red and violet. 



5 



487-1 



4 (6) 





1 



484-8 





Middle of dark space ; breadth, 3 '6. 



* A companion on either side l^mmm- off. 



t One very bright line missed (according to note-book) near .F towards the red. 



