FLAMES OF COMPOUNDS OF CARBON AND HYDROGEN. 427 
TaszE I. Observations of the Angle of the Prism. 
Serzes I. Serizs II. 
a -——_————————ssssi—i—iH | Total Number} Mean of all the 
Number of | Mean of the Obser- | Number of | Mean of the Obser- |°f Observations. Observations. 
Observations. vations. Observations. vations. 
60° 0’ 15” 60° 0’ 18” 60° 0’ 16” 
| Taste II. Observations of the Solar Spectrum. 
— Sunes TL eae Orem 
eee Number of Number of ot ens Total Num: 
eee meron tare niin | SLO Spee 
3 47° 20’ 27” 3 47° 20' 21”) 0’ 6” 6 47° 20’ 24” 
2 47 29 54 4 47 30 2/0 8 6 47 29 59 
2 47 39 52 3 47 39 51/0 1 5 47 39 51 
2 47 50 22 3 47 50 10/0 12 5 47 50 12 
ie bbe Hee 1 48 0 50 1 48 0 50 
2 48 18 15 4 48 18 12);0 3 6 48 18 13 
2 48 55 24 4 48 55 26);0 2 6 48 55 25 
t 4 49 45 5 49 1 44];0 1 9 49 1 465 
h 2 49 37 1 49 2 35);0 2 3 49 2 36 
2 49 2 55 3 49 56|}0 1 5 49 55 
2 49 29 9 3 49 29 19;0 10 5 49 29 15 
ot 4 49 49 2 4 49 49. 2 
2 50 35 2 3 50 385 5/0 8 5 50 35 
if 51 34 50 6 51 34 43] 0 7 51 34 44 
. ‘ Mean Temp. of Prism, 64-2 F. 
Mean Temp. of Prism, Se F. Mban Meme. of Air aE 
penn ches IUCN ism neasay sb) 6) Pals 
* ©, and F, are used here to denote very strong lines adjacent to FRAUNHOFER’S lines, C and F. 
P- t FRAvunHOFER denotes by 6 the two most refracted lines of a remarkable group, represented by three stron g lines 
‘in his map of the solar spectrum. I have here denoted these lines by b, b,, by, in the order of their refrangibility. 
_ On 20th May, about 7" 10™ p.m., when the sun was rather low in the horizon, but free from clouds, I observed 
; with a power of 21, the line b, to be very finely but distinctly double, so that the group consists of four lines. 
‘ 
VOL. XXI. PART III. 5 Zz 
