TAKEN AT AVAXSFORD HOUSE, WATFOEP, 1878. 



Ill 



afloptcd moan and the mean of the maximum and minimum read- 

 ings the ditference in the year is only U°- 1 . 



In accordance with the suggestion made hy Mr. Greaves in his 

 recent Anniversary Address as President of the Meteorological 

 Society,* I have added a column headed " diyness." It expresses 

 the ditference between the temperature of the air and the temper- 

 ature of the dew-point at 9 a.m. The dew-point temperature can 

 therefore be readily ascertained ; and from the values given in the 

 table can be calculated, for 9 a.m., all the values here omitted, re- 

 lating to tlie state of the air, which are given by Mr. Glaisher in 

 his " Remarks on the AVeather " in the Quarterly Ileports of the 

 Hegistrar-General, namely, mean pressure of dry air reduced to 

 sea-level, moan weight of vapour in a cubic foot of air, mean addi- 

 tional weight required for saturation, and mean weight of a cubic 

 foot of air. 



In the second table the principal alteration is in the arrangement 

 in three principal sections relating to rainfall, cloud, and wind. 

 Columns showing the number of days of clear sky and overcast 

 have also been added. 



In the following summary of the principal results for the different 

 seasons, December to February are considered as Winter mouths ; 

 March to May as Spring ; June to August as Summer ; and Septem- 

 ber to November as Autumn. 



"\Yatfoed. 



For comparison the results of observations at the Greenwich 

 Observatory are computed as before. 



GnEENWICH. 



' Quart. Journ. Meteorological Society,' vol. v, p. 103. 



