338 NATURE AND MAN. 



the western coasts of North-western Europe that the amelioration 

 of its winter climate is due to the afflux of water of a temperature 

 considerably higher than that of the air. It has been urged with 

 conclusive force by Admiral Irminger (of the Danish Navy) that 

 nothing else can account for the openness of the fiords and harbours 

 of the indented coast of Norway, even beyond the North Cape, 

 through the whole winter ; whilst the opposite coast of East 

 Greenland, ranging, like it, between the parallels of 60° (that of 

 the Pentland Firth) and 72° N., is so blocked with ice throughout 

 the year as only to be approachable in exceptional summers. 

 And this view has derived full confirmation from the observations 

 systematically carried on under the direction of Professor Mohn 

 of Christiania (the able director of the Meteorological Department 

 of Norway), which have shown how completely dependent the 

 temperature of the coast-line is upon that of the sea which laves 

 it. For while the temperature of the air is generally much below 

 the freezing-point during the winter months, that of the water 

 is always considerably above it; the average excess at Fruholm, 

 near the North Cape, being as much as 14^° Fahr, And it has 

 been further shown by Professor Mohn that not only the coast- 

 temperature of Norway during the winter, but its inland climate, 

 is affected in a very marked manner by this afflux of warm water ; 

 for the " isocheimals," or lines of mean winter-temperature, instead 

 of corresponding with the parallels of latitude, lie parallel to the 

 coast-line. 



How, then, are these phenomena to be explained ? If the vis 

 a iergo of the Gulf Stream has spent itself in the mid-Atlantic, what 

 force brings this afflux of warm water to our shores, and carries it 

 on to the north-east, along the coast of Norway, and even past the 

 North Cape to Spitzbergen and NovaZembla? And how does 

 it happen that the water that laves our north-western shores in 

 winter is not only so much warmer than the air which rests upon 

 it, but continues to preserve a notable portion of that warmth, at 

 least as far as the North Cape, notwithstanding that as it flows 

 northwards its temperature is more and more in excess of that of 

 the atmosphere above it ? 



It is obvious that the continual outflow of the deeper stratum 

 of Polar water, of which we have evidence in the constant main- 



