Intelligence and Miscellaneous Articles. 487 



more diffused on one side than on the other ; that of the dark red is 

 a little difficult, especially if the air is not very pure. In this case 

 the observations were somewhat multiplied. The following numbers 

 are the result of at least three measurements. Those taken in suc- 

 cession usually agree better with each other than those taken on 

 different evenings ; perhaps we have here the same phenomenon as 

 in the case of the double stars. 



I shall first give the results obtained for the terrestrial atmosphere, 

 and then those of Jupiter, and I shall refer the position of the bands 

 to the darker line of the band D. 



Relative position of the Terrestrial Atmospheric Rays. 

 D-C 6 . D-C. D-B. 



Julv 16 1*85 2-85 3*95 



20 275 3-95 



20 1-70 2-72 4*11 



21 1-76 2-73 3-99 



20 (Moon) .. 2-03 £93 



Mean. .. T77 2"74 3'9S 



For Jupiter I shall call D', y, ,3 the lines analogous to those of the 

 terrestrial atmosphere D, C. B. The following are the intervals : — 



Intervals of the Bands of Jupiter. 



D'-y. D'-3. 



Julv 17 1\90 3-70 



17 1-90 4-00 



19 1-98 3-49 



20 1-83 3-79 



20 2-02 3-55 



21 T93 3-_7S 



Mean 1'92 377 



It is seen by these measurements that the bands y and fi of 

 Jupiter do not coincide in position with those of the terrestrial 

 atmosphere, but that the two, C and B, approach to some extent. 

 Their relative distance is also different ; for we have 



C -B = 2 r -21, while y-p=l r -5. 



Their difference exceeds all possible limit of error. 



Hitherto we have only compared lines with each other as to their 

 relative place ; but it is interesting to see if the starting-point is the 

 same — that is, if the line D in Jupiter coincides with D in the atmo- 

 sphere. Several micrometric measurements gave a constant difference 



