68 
Mr. Heelis, F.RA.S., read a paper “On some recent 
results of Observations of the Specific Gravity of Sea Water.” 
(This paper was afterwards read at the Ordinary Meeting of 
the Society held on December 26th. See page 55.) 
Mr. Vernon, F.R.A.S., exhibited a diagram showing the 
excessive amount of barometric and thermometric oscillation 
which had occurred during the month of November, 1866. 
January 3rd, 1867. 
E. W. Binney, F.RS., F.G.S., President of the Section, 
in the Chair. 
“On the Mean Weekly Temperature at Old TrafFord, 
Manchester, for the seventeen years 1850 — 1866,” by G. 
V. Vernon, F.R.A.S., F.M.S. 
As I am not aware that there have been any carefully de- 
duced values of the mean temperature of this neighbourhood, 
perhaps the data accompanying this paper may serve until 
such time as a more extended series can be obtained. I may 
state that the thermometers used have all been standard 
ones compared at Greenwich, and all the observations have 
been reduced to that standard. The thermometers are placed 
upon a stand 4 feet from the ground, and carefully protected 
from radiation and other disturbing influences. 
The unavoidable omissions in my register I have been 
enabled to supply by the kindness of my friend Mr. J ohn 
Curtis, F.M.S!, whose thermometers are placed similarly to 
my own, and within a very short distance from my station. 
The mean values have generally been determined from the 
readings of the maximum and minimum thermometers in 
the shade combined with readings of a standard thermometer 
read once a day ; these observations being all made at 8 a.m. ; 
in reducing them Mr. Glaisher’s corrections for diurnal range 
have invariably been applied. Whilst upon this subject I 
