'290 



METEOROLOGY AND ALLIED SUBJECTS. 



for Pekin is directly opposed to that for Western Europe ; similarly 

 the annual curve for Sitka is directly opposed to that for Norway. A 

 chart of the world, showing lines of equal annual cloudiness (isonephelic) 

 is given by Eenan, and although only a first approximation to the truth, 

 yet it seems to justify the statement that for the whole earth the 

 average cloudiness is not much above 50 per cent., possibly as high as 

 55 per cent. {Z. 0. 0. 31., XVI, 1881, p. 102.) 



Schiaparelli has comj)uted the annual diurnal period of moisture from 

 observations made during thirty years at the observatory at Milan. 

 He finds the variation of relative humidity is, as in nearly every other 

 place, the converse of that of the temperature, as is shown by the follow- 

 ing table: 



Month. 



So. 



Relative humidity. 



Range. 



Mean. 



December. 

 January .. 

 Tebruary . 



March 



April 



May 



June 



July 



August . . . 

 September 

 October . . . 

 November 

 Tear 



+0.7 



-0.5 



+0.6 



3.1 



6.7 



10.6 



13.8 



15.7 



15.6 



13.4 



9.3 



4.4 



7.8 



4.8 

 4.4 

 4.8 

 3.7 

 7.3 

 9.5 

 11.8 

 13.3 

 13.2 

 11.5 

 8.8 

 6.3 

 8.5 



7.7 

 7.4 

 15.7 

 20.8 

 23.9 

 25.1 

 25.6 

 26.1 

 26.0 

 25.2 

 18.7 

 13.5 



87.5 

 86.7 

 80.4 

 72.7 

 68.8 

 67.9 

 65.3 

 62.4 

 65.0 

 72.7 

 79.9 

 84.6 

 74.5 



{Z. 0. G. M., Vol. XV, 1880, p. 417.) 



VII. — MOVEMENTS OF THE ATMOSPHERE, WINDS, ETC. 



Woeikof, the author of the concluding chapter of Professor CofiBn's 

 "Winds of the Globe," has given a review of his results with some 

 modifications, from which we extract the following table relative to winds 

 in Greenland: 



stations. 



Prevailing -winds. 



Summer. 



Winter. 



Polaris Bay House 



Port Foulke 



TJpemavik 



Godthaab J"acobhaven 

 Sabine Island 



>rE. and SW. 

 NE. and SW. 

 N. andSW... 

 E. andSW... 

 N. and S 



NE. and E. 



NE. 



N. and E. 



E. 



N. 



He concludes that we can assume with great probability that in win- 

 ter a very strong current of air from Northern Greenland blows along 



