. Meteorological f and Essa 
Atmospheric Origin of the Aurora, §. « 145 
Anr. XIU.—On the-Atmospheric Origin-of the Aurora and its 
- Connexion with the Crystallization of Snow ; by B.-F. Josua,. 
_M. D., of the city of New York, and late Professor of Natural 
Philosophy, & é&c. in oe College, Schenectady. 
New York, 122 Bleecker street, Aug. 17th, 1838. 
TO PROF. SILLIMAN. 
Views Sir,"There appears to be i increasing evidence of an in- 
timate connexion between the aurora and atmospheric vapor, a 
connexion which has not been wholly overlooked by recent ob- 
servers. Recent epochs may have been more favorable to its ex- 
hibition in the middle latitudes. In the two brief notices of the 
aurora in the Transactions of the British Association, which met. 
in August, 1837, this is the most prominent eae. In one, 
Dr. Traill describes the contemporane dts exhibition of station- 
ary cirri and auroral streamers, aid, in’ the other, Mr. Herapath 
attempts to refer the aurora to the precipitation, of | aqueous vapor. 
Still earlier, in your own respectable Journal, in a notice of my 
theory, published in 1836, there was an implied acknowledgment 
of the existence of some. kind of auroral vapor, and even of its 
magnetic properties. 
In March, 1836, there were published Observations on fifty six 
Auroras, seen by me at Schenectady, N. Y., within the five pre- 
ceding years, and some hew views as to the connexion Lee 
this meteor and clouds, rain and snow. 
The author desires to avail himself of the Sides circulation of 
the Journal of Science to communicate to the public some of the 
4 sults, to add others in confirmation of the same views, 
and ‘to correct r rrect a misapprehension which may prevail in relation to 
the elevation which he assigns to this meteor.t ~The small ele- 
vation which he is supposed to have assigned it is the only objec- 
tion which he has seen made to his views. 
* Vide —_— No. .2, to the Repott of in Regents of the University of the 
State of New -York, and the same in a ae phlet of sixty nine Pages, entitled 
or the sake of convenience, the ae meteor will be used in its more com- 
prehensive sense. 
a No. 1. 19 
