View report page

21
From this it will be seen that the mean temperature
of the air in the city has been about half a
degree below the average for the last ten years, and,
as usual, it has been about, 2.5 degrees above the
mean temperature of Greenwich—the largest difference
being in the Autumn quarter, when the mean
temperature in the city was 48.1, that at Greenwich
being 43.0. The average temperature at which dew
has been deposited from the air has been 48.2
degrees in the Autumn quarter, 36.5 in the Winter,
48.2 in the Spring, and 51.6 in the Summer; and
the degree of humidity has ranged from 68 (saturation
being 100) to 86—the average for the whole
year being 77, against a mean of 80 degrees for
the last ten years. This comparative dryness of the
atmosphere is referable to the small rainfall of the
year, it having been but 17.95 inches, instead of
24.47; and the number of wet days has been 118
instead of 169. The first quarter of the year (that
ending in December, 1869) was rather wetter than
usual, but all the others have been drier—the total
rainfall, for example, in the quarter ending in March,
was but 3 92 inches, against an average of 6.08
inches, and that of the following Spring quarter was
but 1.64, instead of 5.91. These circumstances have
doubtless had their influence on the public health;
for dry and warm seasons are nearly always salubrious.