[In She preceding Tables I. to XII., the mean temperature of the air 
fthown for every day in 44 years, and in the forty-sixth column 
Hfchese Tables the mean temperature of every day is determined. 
m taking the differences between the mean temperature of every day, 
ifrom the average of the same day as found from all the years, the 
excess or deficiency of every day is shown; and in this way Tables XVI. 
HXXVII. were formed, those days of excess of temperature being 
Kpguished by the sign phis ( + ), and those of defect of temperature 
being denoted by the sign minus (— ). 
■.glance at these Tables shows that the differences from day to day 
are [very great, and that the temperature of the same day is very 
different in different years. At times it will be seen there have been 
long periods together with one or other sign prevailing, but that there 
have been but few months in wliich on every day of the month it has 
been either always above or below the average; the only instances 
are [February 1853, July 1857, and August 1860, during which months 
[every day was cold and of lower temperature than the average; and 
October 1831, in which every day was warm and of higher temperature 
than the average. There are, however, a few having but one with 
gjjher a + or — sign and all the remainder affected with the opposite 
sign; they are:— 
January, 1830 and 1834 
February, 1855 
April, 1844 
June, 1860 
November, 1851 
December, 1852 
■very other month there have been two or more days with different 
*>gns. It will thus be seen how very rarely every day of a month has 
heeii wholly of high or wholly of low temperature. This will be more 
Nearly shown by the following Table:— 
