454 METEOKOLOGICAL REPORT, 1869, 



The 79 years, from 1771 to 1849 inclusive, gives a mean tem- 

 perature (in the latitude of London) of 48"3°, with a variation 

 between one year and another from 45*1° in 1784 to 51-3° in 

 1846. The difference is 6-2°." 



Again : the mean temperatures of the different seasons of the 

 year, as deduced from the records examined for the conclusions 

 stated above, is as follows : — 



"The mean temperature of the spring months, March, 



April, and May, is 46-4°. 



" The mean temperature of the summer months, June, 



July, and August, is 60"0'^. 



"The mean temperature of the autumn months, Sep- 

 tember, October, and November is 49'3'', 



" The mean temperature for the winter months, Decem- 

 ber, January, and February is 37'6°. 



" The mean temperature for the whole year 48-3°." 



The cold of last November gave rise to many speculations as 

 to the probable character of the coming winter. In a paper read 

 before the Manchester Philosophical Society, in 1864, Mr. G. V. 

 Vernon summed up the results of a very close examination of 

 the records of the temperature of November extending over 91 

 years in the following words : — 



" Careful investigation of the mean monthly temperatures for 

 the long period made use of shows that no safe conclusions of 

 any kind can be based upon the character of any particular 

 month. Cold winters succeeding a warm November were very 

 few in number, and in most cases these winters were preceded 

 by a November not much above the average temperature, as in 

 1783, 1794, and 1799, when the mean temperature of November 

 was only 0*5°, 0*9°, and 0'5° respectively above the mean. 



"November 1822 and 1846 were the only two Novembers 

 much above the average which were followed by a cold period 

 immediately afterwards." 



The following statement of the average temperature of the 



