ea 
CI i 
Meteors of November, 1868, 409 
These three suppositions, of two currents in the air, and of 
a downward motion of the cloud, seem to be necessary to any 
explanation of the appearances of the cloud. But they do not 
entirely account for the whorls and changes of form described 
by Miss Colby and others, and so evident in Mr. Gilman’s 
sketches. 
The same were quite remarkable at New Haven also, though 
my sketches were not designed to show them. I only designed 
to show the place of the body of the cloud, relatively to Jupi- 
ter. Mr, Gilman’s sketches, which reached me but a day or 
two after the shower, seemed a remarkably accurate expression 
of my recollection of the shapes of the cloud. 
To account for these whorls and transformations, we ma 
Suppose between these two principal currents of air, or travers- 
ing them, various other currents, These need not necessarily 
be horizontal. But at that distance from the disturbing causes 
cloud imply. We expect greater simplicity in the aerial move- 
ments in these upper regions of the atmosphere, é 
0 attribute these motions of meteor trains to previously ex- 
isting currents, implies, moreover, that complex currents ex- 
tend through the whole thickness of the stratum in which the 
Cloudy trains are developed. For in all cases of a persistent 
Tescent matter, shortly after the flight of the meteor. — 
& system of currents previously existing in the air is 
probable. 
cloud, we see the same coiling motions of the line of gee a 
uc 
not 
co 
not be easily reduced to system, 
this is a true explanation, the mass of the meteor must 
have been sufficient to set in rapid motion the air that fills 
hundreds of cubie miles of space, as well as to develop light 
and heat. What kind of matter it is which remains visible in 
the cold upper air for three-fourths of an hour, until by grad- 
ual dissipation the light faded out, I leave for others to say. 
Am, Jour. Sc1.—Szconp Series, Vou. XLVI, No. 141.—May, 1869, 
27 
% 
