290 Recent contributions to Astro-Meteorology. 
2. Influence of the August and November meteors upon the temperature 
of the atmosphere. 
Erman early asserted the existence of cold periods, from the 5th 
to the 12th of February, and from 10th to the 13th of May. 
These he attributed to the influence of the August and Novem- 
ber meteors, assuming that they passed at those epochs between 
the earth and the sun. To the same cause he attributed certain 
dark days, and other appearances, said to have occurred in the 
years, A.D. 1106, 1206, 1208, 1706, and 1547. 
In a series of papers read before the Paris Academy of Scien- 
ces, and published in the Comptes Rendus,* Mr. Ch. St. Claire 
Deville has given the results of an elaborate investigation of the 
alleged abnormal changes of temperature in these months, as 
well as those alleged for corresponding days of August and No- 
vember. 
[r. Faye in response to the first of these papers, shows con- 
clusively that the dark days, &c., adduced by Erman, cannot be 
referred with any probability to the meteors as their cause. 
In his earlier papers, Mr. St. Claire Deville undertakes to show 
that there are periodic variations of the temperature of the crit- 
ical days in February, May, August, and November, that corres- 
pond to secular maxima and minima of the August and No- 
vember meteors. For the August meteors he assumes a maxX!- 
mum in 1847 or 1848, relying upon the assertion pf Mr. Coulvier- 
Gravier. 
The existence of a maximum for the meteors in or near those 
a8. $e month, but those corresponding to points 90° apart 
Bas, 
maxima and minima, shall in November be one or two days e- 
fore we reach them, shall in May be at the time of the passage 
of the earth across the plane of the November group, in Au- 
‘ Bes Vol. lx, 577, 655, 696, 909; lxi, 5, 61, 350; Ixii, 1054, 1149, 1209, and Ixiii,, 
