METEOEOLOGY. 



451 



freeze entirely, as tlie winds and tides always break the ice which is 

 already formed 5 thus seas of that kind have, even in the midst of win- 

 ter, a considerable open surface, which evaporates freely. The tempera- 

 ture of the sea surface may be so high that much more rain than snow 

 falls even in winter. Let us take an example: The sea surface between 

 the southwest of England and the south of Ireland has a temperature 

 of above 50° F. even in January. Supposing a saturated stratum of air 

 to rise from these seas, it would have cooled down to about 38o.4 F. at an 

 elevation of 4,000 feet, that is, at the level of the highest peaks of the 

 British islands. The resulting precipitation will be rain and not snow. 

 {Nature, xxv, p. 424.) 



Woeikof discusses the influence of local topographical conditions on 

 the average winter temperatures observed at meteorological stations, in 

 Yol. XIV of the Journal of the Eussian Chemical and Physical Societies. 

 He shows from the Swiss and Siberian observations that the tempera- 

 ture of the air is often much colder in the valley than on the mountains, 

 and that in general the annual range of temperatures is less on isolated 

 mountains than the surrounding countries. These peculiarities must be 

 allowed for, in order to obtain a true estimate of the distribution of tem- 

 peratures. {Nature, xxvi, pp. 190 and 209.) 



Nordenskjold has published the scientific observations made on the 

 voyage of the Vega, which are made accessible to English readers by 

 means of Leslie's translation, j)ublished by MacMillan & Co., 1881. The 

 Vega wintered at 67° 4' 49" north and 173o 23' 2" west. In this locality 

 the thickness of the ice was measured as follows : 



Dec. 1 



Jan. 1 



Feb. 1 



Feb. 15 



Mar. 1 



April 1 



April 15 139 



May 1 154 



Centimeters. 



56 



92 



108 



120 



123 



128 



Centimeters. 



May 15 162 



June 1 154 



June 15 151 



July 1 104 



July 15 (full of holes) . . 67 



July 18 (ice broken up). 



{Natur€,-K^Y, p. 204.) 



, E. D. Archibald, in some remarks on the cold weather of Europe in 

 the spring of 1882, attributes this largely to the influence of floating 

 ice reaching the lower latitudes of the Korth Atlantic Ocean. (He 

 does not, however, make it apparent but that northerly winds may 

 have been the common cause of the low temperatures and the abundant 

 ice.) He adds, "Though I agree with Hann in attributing more impor- 

 tance to the tropical than to the ^oZ«r area in influencing the general 

 weather of these latitudes, I think it very probable, on theoretical 

 grounds, that we are more relatively influenced by the latter area in 

 summer and the former in tcinter, and that just as it has been inferred 

 that the regular recurrence of periods of diminished temperature in 



