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Ordinary Meeting, March 18th, 1862. 
J. C. Dyer, Esq., Vice-President, in the Chair. 
The following communication from Sir John F. W. 
Herschel, Bart., M.A., D.C.L., F.R.S., &c., Honorary 
Member of the Society, was read by Mr. Baxendell: — 
In the report of the Ordinary Meeting of the Literary and 
Philosophical Society for February 18, 1862, I find an 
abstract of a paper “ On the Present State of Meteorology,” 
by Mr. T, Hopkins, M.B.M.S., in which he is reported to 
state that in my recent work on Meteorology I “omit to 
notice the disturbing influence of the liberated heat of con- 
densing vapour on the gases,” and also that in that work I 
“ abandon the old theory of winds ” (meaning, I presume 
from the context, the ILadleian theory,) “ and attribute them 
to the action of aqueous vapour in a new form.” 
With regard to the former of these two statements I beg 
to refer to Art. 53 of that work, where, alluding to the con- 
densation of the vapour in the atmosphere, it is remarked 
that “ in every case, such condensation is accompanied with 
a mitigation of cold at the point where it actuality takes place” 
What effect beyond this the condensation of vapour can pro- 
duce on the gases I am at a loss to understand. It can in 
no case give rise to an actual elevation of temperature above 
that of the mixture of air and vapour which may be intro- 
duced into any mass of cold air and which may thereby effect 
a partial condensation. It. can only act in mitigation of the 
chilling effect of such admixture on the introduced portion 
which would arise were the vapour not condensed. Inasmuch, 
however, as its condensation and precipitation as rain 
diminishes pro tanto the total barometric pressure, and there- 
fore allows both air and vapour to flow in from other quarters , 
Proceedings— Lit. & Phir. Society— No. 13.— Session 1861—62. 
