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A CATALOGUE OF OBSERVATIONS OF LUMINOUS METEORS. 147 
predominate, and that the compound blue-coloured meteors are twice as 
numerous as those of a pure yellow and red colour ; a result contrary to that 
obtained from the preceding observations in China. We observe that the 
meteors comprised in the tints belonging to the lower part of the spectrum, 
from green to red, are in number 465 cases, while those comprised in the 
tints of the upper part of the spectrum, from green to violet, embrace 401 
cases. Now, in applying to the colouring of shooting stars and globes the 
theory of M. Charles Doppler on the colour of single fixed stars, of the 
double stars, and stars periodically variable, it would be necessary to con- 
clude from the facts, that 64 coloured meteors have been moving from the 
observer, from the moment of their appearance ; supposing, which is not 
always the case, that the meteors have followed the right line which joins 
them with the eye of the observer. However, on the other hand, meteors of 
a pure blue, which are of an ascending tint and approach towards the observer, 
are twice as numerous as those of a pure red and yellow, which belong to 
the descending tints and recede from the observer. According to the 
theory of M. Doppler on the colour of fixed stars, an object luminous by 
itself, or from a borrowed light, increases in intensity as it approaches the 
observer, while the colour passes, rapidly ascending from white to green, then 
to blue, and at last to violet. By receding, the intensity diminishes in all 
cases, and the white light passes successively to yellow, to orange, and at last 
to red. Perhaps we ought still to take account, in the colour of fixed and 
shooting stars, of the differences of perception and appreciation of luminosity 
and colour, of different observers. 
(3) Colours of shooting stars and globes observed at Paris from 1841 to 
1843, with notices of trains, fragments, &c., differently coloured, observed 
in China as well as in England. 
(Brom the Comptes Rendus, xliv., Jan. 12, 1857.) 
The author now proceeds to give a list of coloured shooting globes ob- 
served at Paris fiom 1841 to 1853 by M. Coulvier-Gravier*. This skilful 
observer has given with great precision as many as three or even four suc- 
cessive shades assumed by meteors in their transit through the air. These 
tints almost entirely follow the law deduced by M. Doppler +}, on the variation 
of colour of a luminous point in motion. The greater part of the shooting 
globes appear blue on approaching the horizon or the observer, after having 
passed through all the tints corresponding to the upper part of the spectrum. 
Some terminate with red, probably in receding from the observer. Besides 
the law of M. Doppler, which may be applied to the colours of meteors, we 
ought still to take account of the particular state of the atmosphere in a 
twofold point of view, as regards electro-chemistry and the modificators of 
meteorological agents. 
Colours of globe meteors observed at Paris from 1841 to 1843, 
January.—Bluish; bluish towards the horizon, 2 cases. 
February.—Bluish ; bluish towards the horizon, 2 cases ; fragments yellow, 
red, then greenish-yellow globe, and three fragments bluish towards the 
horizon. 
March.—Yellow-orange, then green; bluish towards the horizon. 
- April.—Bluish towards the horizon; white, orange-yellow, orange, then 
blue-green. 
May.—Bluish towards the horizon; white, then bluish towards the hori- 
zon; clear yellow, then bluish; clear yellow, then yellow-orange. 
* Annales de Chimie et de Physique, vol. xl. (January 1854). : 
tT Répertoire d’Optique Moderne de M. l’Abbé Moigno, 3rd part, p. 1165-1208, 
LZ 
