ON THE TEMPERATURE OF NOVEMBER. 



427 



XXXI. Examination of the Truth of the Assertion, that when 

 November has a Mean Temperature above the average, it is 

 usually followed by excessive Cold between December and 

 March following. By G.V.Vernon, F.R.A.S., M.B.M.S. 



Bead before the Physical and Mathematical Section, January 7th, 1864. 



In the Table accompanying this paper I have tabulated all 

 the Novembers from 1771 to 1861 which had a mean tempe- 

 rature above the average, and in the columns adjoining have 

 given the differences between the mean temperatures of the 

 four following months of December, January, February, and 

 March and their mean values. 



We find, by classifying the months above and below the 

 average, the following figures : — 



Months. 



Number of 

 months 



above the 

 average. 



Number of 

 months 



below the 

 average. 



December ..,. 



as 



2Z 

 21 



23 



1 



19 

 20 

 16 



January 



February 



March 





Sum 



9X 



70 





or 91 months above the average against 70 months below 

 the average, following a November with a mean tempera- 

 ture above the average. 



Out of the entire series, there are 6 years in which a 

 November above the average was succeeded by 4 consecu- 

 tive months also above the average temperature, and only 

 2 years in which a warm November was followed by 4 con- 

 secutive months below the average. 



In place of a warm November preceding excessive cold, 

 we find that in most of the years in which severe frosts 



