a 
106 British Association for the Advancement of Science. 
a whirlpool. The general correctness of this view was shown 
by the fact that Mr. Redfield’s and Col. Reid’s whirls were found 
- to advance along the course of the gulf-stream, the warmth of 
which tended to load the air above it with vapor ; and in the hur- 
_ricane which did such damage to Charleston, the town was saved 
from destruction by the fact that the most violent part of the 
storm followed the bend of the river: the shipping was nearly 
destroyed. In this way was also to be accounted for, the perplex- 
ing fact that the storm was propagated against the course of the 
wind, as is well known also in summer thunder storms. These 
were the phenomena of dry storms. When much rain fell, the 
space above was left arid also by the descent of the water, while 
the air below was pushed out on all sides, thus very much modi-_ 
_ fying the current at the surface, 1 increasing the force to leeward, , 
. ae it to windward, causing sometimes the fearful | 
sultry calm preceding the Buiter storm ; the fall of tempe- 
rature above, in consequence of the supneiiiin of the air rushing © 
in to fill the void, often froze into hail the rain-drops as they 
passed through, the surface of the boles of which would be clear 
ice ; but, expanding as it formed the shell, the inner part would 
.” be sitio and crystalline, because partly woth Mr. Espy, of Phil- 
‘adelphia, had a theory nearly the reverse of this: he eonceived 
“the heat given out by the vapor in passing to the state of cloud 
or rain, to be so abundant, as, by its rarefying influence to cause 
a rapidly ascending column or vortex, capable of producing most 
appalling effects; and the only step doubtful in this theory was 
the first,—for pelted the vapor can pass to the state of water, it 
must be robbed of this very latent heat by an external cause ; but, 
grant this first step, and the rest of Mr. Espy’s theory was almost 
a series of mathematical demonstrations. 
A valuable paper was then read, “on certain results which he 
had recently arrived at, respecting the minimum thickness of the — 
crust of the globe, which might be consistent with the observed 
phenomena of Precession and Nutation, assuming the earth to 
have been originally fluid,” by Mr. W. Hophiaet 
Mr. Smythies then communicated a general method of solving 
_ dynamical problems relating to the motion of free bodies, by — 
Means af. Gitretustian and elimination of differentials without — 
tion, by v 
any integration, which the result is obtained in a finite number 
of sipeienséan erms, when the equations of condition determin- 
ing pe motion are algebraically assigned. 
Sl 
2 . Fs 
ee a Ses, oP ‘ ce ee 
