79 
when the colder of the extreme of the winter months has 
not yet been entered upon, viz., the month of March. In a 
meteorological sense winter may be considered as including 
five months of the year, viz., November, December, Janu- 
ary, February, and March. But January, so far as low 
temperature is concerned, is the pivotal month of the 
winter, and March has a mean temperature slightly below 
that of November. The difference is so small, only about 
0-7 deg. Fahr., that in comparing the mean temperature of 
winters the mean temperature of these two months may be 
practically neglected. The mean temperatures deduced 
from my own observations extend over only 17 or 18 years; 
but the late G. V. Yernon, Escp, F.B.A.S., was kind enough 
to furnish me with the weekly temperatures he had deduced 
from the year 1850 onwards till 1861, when I began to 
make my own observations and deductions. That the mean 
temperatures here presented may have a common basis I have 
calculated them upon the weekly mean temperatures of the 
last 29 years, which of course include those of the late Mr, 
Yernon. 
The results are as follows for the winters extending from 
the first week of December in one year to the last com- 
pleted week in February of the year following. 
Winter of 
.Mean 
Temp. 
Winter of 
Mean 
Temp. 
1850-1 
... 40 - 3 ° 
1865-6 
... 41 - 9 ° 
1851-2 
... 39 ’ 8 ° 
1866-7 
... 39 - 9 ° 
1852-3 
... 39 * 9 ° 
1867-8 
... 400 ° 
1853-4 
... 37 - 3 ° 
1868-9 
... 43 * 6 ° 
1854-5 
... 35 - 1 ° 
1869-70 
... 37 - 1 ° 
1855-6 
.. 37 - 3 ° 
1870-1 
... 35 - 6 ° 
1856-7 
... 37 * 9 ° 
1871-2 
... 40 ’ 3 ° 
1857-8 
... 39 - 4 ° 
1872-3 
... 39 - 2 ° 
1858-9 
... 41 - 0 ° 
1873-4 
... 40 * 6 ° 
1859-60 
... 35 - 4 ° 
1874-5 
... 38 - 6 ° 
1860-1 
... 36 - 4 ° 
1875-6 
... 38 - 8 ° 
1861-2 
... 39 - 3 ° 
1876-7 
... 42 - 3 ° 
1862-3 
... 41 - 9 ° 
1877-8 
... 39 - 6 ° 
1863-4 
... 37 * 9 ° 
1878-9 
... 31 * 4 ° 
1864-5 
.. 36 - 6 ° 
