1915- ^o- 5 ROALD Amundsen's ANTARCTIC expedition: meteorology. 31 



The Tension of Aqueous \'apour. 

 Taking the means of the Tensions at 8 a. m. and 8 p. m. as the 

 monthly means of the tensions of vapour, we get 



Maximum in December, Minimum in August. Range 2.4 — o.i or 

 2.3 mm. The highest observed is 4.4 mm. in December. The lowest 

 tension observed does not reach o. i mm. A diurnal period is seen only in 

 the warmest months with a slight excess of 0.2 mm. at 2 p. m. over the ten- 

 sion at 8 a. m. and 8 p. m. 



Atmic Wind -Roses, mm. 



The wettest winds are N and X\V, the driest is South. Difference 

 0.8 mm. The predominating East wind is rather wet. The east winds 

 seem to be chiefly incurved cyclonic winds coming from the sea. 



The Relatixe Humidity. 

 Monthl}'. Means. Per Cent. 



Maximum in July and August. Minimum in November. Range 90 — 73 

 or 17 per cent. A ver\' little diurnal period is visible. 



