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PHYSICAL AND MATHEMATICAL SECTION. 
February 27th., 1862. 
Mr. Baxendell, E.R.A.S., read a Paper “ On the Relations 
between the Decrement of Temperature on Ascending in the 
Atmosphere and other Meteorological Elements.” 
According to the theory which attributes the production of 
winds and storms to upward currents of air, caused by the 
heat liberated during the condensation of aqueous vapour 
into clouds and rain, the rate of decrease of temperature on 
ascending in the atmosphere ought to he less in rainy than 
in fair weather ; and the reasonings and calculations of Dr. 
Win. Thomson, in his valuable Paper “On the Convective 
Equilibrium of Temperature in the Atmosphere,” lately read 
to the Society, point to the same conclusion ; but in a Paper 
entitled “Remarks on the Theory of Rain,” read to the Section 
on the 29th of March, 1860, the Author gave some results 
derived from a discussion of the Greenwich and Oxford obser- 
vations, which seemed to militate against this theory, and 
reference was made to the fact stated by Ksemtz and others, 
that the diminution of temperature on ascending in the 
atmosphere is more rapid in rainy than in fine weather. It 
appears, however, that this fact is not generally admitted by 
meteorologists, as the observations from which it is derived 
were mostly of a desultory nature, and continued for only 
short periods of time. The Author, therefore, thought that 
a discussion of the monthly results of the observations made 
during the years 1848-58, at Geneva and on the Great St. 
Bernard, given by Mr. Vernon in his valuable Paper “ On 
the Irregular Barometric Oscillations” at those places, 
might throw some light on the subject, and, at the same 
time, serve to indicate the relations which exist between the 
decrement of temperature and other meteorological elements, 
a branch of meteorologv which has hitherto been almost 
entirely neglected. 
Tables are given, containing the comparisons of the 
