1898-1902. No. 4.] FORCE OF VAPOUR. ANNUAL PERIOD. 



171 



FORCE OF VAPOUR. ANNUAL PERIOD. 



The following Table contains the monthly means of the force of 

 vapour. For those months for which there are complete observations, 

 the numbers are the same as those in the Table on pp. 168—169. 

 For the other months — except August 1899 — the observations taken 

 on board the Fram, while she was under way not far from the winter 

 stations, have been taken to complete the observations for the respective 

 months. The means thus found are inclosed in brackets. 



The mean for the year is 1.72 mm. 



The monthly means show a fairly even progression, with the excep- 

 tion of February, which is rather high. The year 1900, in particular, 

 gives a remarkably high number. This month also exhibits, as we 

 have seen, p. 116, a particularly high temperature. 



Smoothing the numbers for January, February and March, we 

 obtain the numbers headed 'Sm. 



The smoolhed numbers give, by a parabolic formula. 

 Minimum January 14"' 0.31 mm. 

 Maximum July 20"> 4.81 mm. 

 Range 4.50 mm. 



