26 FARTHEST NORTH 



ice, from which the evaporation is but trifling; and, 

 in the next place, the comparatively low temperature 

 in these regions prevents any considerable evaporation 

 taking place even from open surfaces of water. The 

 moisture that produces this rainfall must consequently in 

 a great measure come from elsewhere, principally from 

 the Atlantic and Pacific oceans, and the amount of 

 water which thereby feeds the Arctic Sea must be very 

 considerable. If we possessed sufficient knowledge of 

 the rainfall in the different localities it might be exactly 

 calculated.* 



" The importance of this augmentation appears even 

 greater when we consider that the polar basin is com- 

 paratively small, and, as has been already remarked, very 

 shallow; its greatest known depth being from 60 to %o 

 fathoms. 



" But there is still another factor that must help to 

 increase the quantity of water in the polar basin, and 

 that is its own rainfall. Weyprecht has already pointed 

 out the probability that the large influx of warm, moist 

 atmosphere from the south, attracted by the constant 

 low atmospheric pressure in the polar regions, must en- 

 gender so large a rainfall as to augment considerably 



* Since writing the above I have tried to make such a calculation, and 

 have come to the conclusion that the aggregate rainfall is not so large as 

 I had at first supposed. See my paper in The Noywcgian Geographical 

 Society's Annual, III., 1891-92, p. 95 : and The Geographical Jom-nal, Lon- 

 don, 1893, p. 5. 



