428 



MR WILLIAM SWAN ON THE PRISMATIC SPECTRA OF THE 







Table III. Observations of the Carbohydrogen Spectrum.. 







Si 



;ries I. 



Series II. 



Difference 

 of Means 

 I. and II. 



Collected Observations 

 of Minimum Deviations. 



Line of the 

 Spectrum. 



Number of 

 Observa- 

 tions. 



Mean 

 I. 



Number of 

 Observa- 

 tions. 



Mean 

 II. 



Total Num- 

 ber of Ob- 

 servations. 



Mean of all the 

 Observations. 



a 



5 



48° 18' 14" 



2 



48° 18' 13" 



0' 1" 



7 



48° 18' 14" 



(3 



3 



48 32 9 



6 



48 32 7 



2 



9 



48 32 7 



ft 



. i • 





9 



48 35 12 





9 



48 35 12 



ft 







9 



48 37 50 





9 



48 37 50 



ft 



. . . 





9 



48 40 10 





9 



48 40 10 



7 



9 



49 3 35 



4 



49 3 31 



4 



13 



49 3 34 



7i 



... 





9 



49 6 23 









5 



2 



49 41 58 



6 



49 41 58 







8 



49 41 58 



*, 







9 



49 44 48 





9 



49 44 8 



^ 2 





... 



9 



49 46 37 





9 



49 46 37 



s 3 







9 



49 48 41 





9 



49 48 41 



€ 







4 



50 27 54 





4 



50 27 54 



I 



3 



50 35 37 



6 



50 35 28 



9 



9 



50 35 33 





Mean Temp 

 Mean Barom 



of Prism, 53° F. 

 ., . . . 30-02 



Mean Temp, of Prism. 62-6 P 

 Mean Temp, of Air, 60-4 

 Mean Barom. . . 29-56 







In Table III., the deviations of the lines a, /5, y, 2, and £, were alone determined by the theodolite ; the other line6 

 were then referred to a, /3, &c, by micrometer observations. 



Table IV. Comparison of Contiguous Lines in the Solar and Carbohydrogen Spectra. 



Solar Spectrum. 



Carbohydrogen Spectrum. 











C 

 3 



Deviation 

 (D.) 



Index of 

 Refraction (p,.) 



a 



3 



Deviation 

 (D.) 



Index of 

 Refraction (/«,.) 





D 



48° 18' 13" 



1-621079 



a 



48° 18' 14" 



1-621083 



D«-D D 



0' 1" 



fx*—f* 



0-000004 



h 



49 2 55 



1-628659 



7 



49 3 34 



1-628769 



L\-D* 2 



39 



fXy-Hb 2 



0-000110 



*i 



49 49 2 



1-636407 



^3 



49 48 41 



1-636349 



D Fl -Ds 3 



21 



fx F -fn 3 



0-000058 



G 



50 35 4 



1-644068 



I 



50 35 28 



1-644147 



D ? -D G 



24 



M?-Ma 



0-000079 



