496 The National Geographic Magazine 



river finds its way to the Indian plains, 

 and this still remains for the future to 

 unravel. 



RECENT STUDY OF THE OCEANS HAS 

 BROUGHT MUCH TO LIGHT 



It is of the ocean, more than of any 

 other physical feature of our globe, 

 that our knowledge has increased of late 

 years. Forty years ago we were pro- 

 foundly ignorant even of its depth, with 

 the exception of a few lines of sound- 

 ings then recently taken for the first 

 submarine telegraph cables, and conse- 

 quently we knew nothing of its real vast 

 bulk. As to the life in it and the laws 

 which govern the distribution of such 

 life, we were similarly ignorant, as of 

 many other details. 



The Challenger expedition changed 

 all this, and gave an impetus to oceano- 

 graphic research which has in the hands 

 of all nations borne much fruit. 



Soundings have been obtained over 

 all parts of the seas, even in the two 

 Polar seas ; and, though much remains 

 to be done, we can now form a very 

 close approximation to the amount of 

 water on our earth, while the term ' • un- 

 fathomable ocean" has been shown to 

 have been based on an entire miscon- 

 ception. Biological research has also 

 revealed a whole world of living forms 

 at all depths, of the existence of which 

 nothing was known before. 



In my former address, eleven years 

 ago, I gave many details about the sea, 

 of which I will only repeat one — which 

 is a fact that every one should know — 

 and that is that the bulk of the ocean 

 is about fourteen times as great as that 

 of the dry land above water, and that if 

 the whole of that land were thrown into 

 the Atlantic Ocean it would only fill 

 one- third of it. 



Eleven years ago the greatest depth 

 known was 4,700 fathoms, or 28,000 

 feet. We have since found several places 

 in the Pacific where the depth is nearly 

 5,170 fathoms, or 31,000 feet, or some- 



what higher than Mount Everest, which 

 has been lately definitely shown to be 

 the culminating point of the Himalayas. 

 These very deep parts of the ocean are 

 invariably near land, are apparently in 

 the shape of troughs, and are probably 

 due to the original crumpling of the 

 earth's surface under slow contraction. 



THE EFFECT OF THE SEA UPON 

 CLIMATE 



The enormous area of the sea has a 

 great effect upon climate, but not so 

 much in the direct way formerly be- 

 lieved. While a mass of warm or cold 

 water off a coast must to some extent 

 modify temperature, a greater direct 

 cause is the winds, which, however, are 

 in many parts the effect of the distribu- 

 tion of warm and cold water in the 

 ocean perhaps thousands of miles away. 

 Take the United Kingdom, notoriously 

 warm and damp for its position in lati- 

 tude. This is due mainly to the preva- 

 lence of westerly winds. These winds,, 

 again, are part of cyclonic systems prin- 

 cipally engendered off the coasts of 

 eastern North America and Newfound- 

 land, where hot and cold sea currents,, 

 impinging on one another, give rise to 

 great variations of temperature and! 

 movements of the atmosphere which 

 start cyclonic systems traveling east- 

 ward. 



The center of the majority of these 

 systems passes north of Great Britain. 

 Hence the warm and damp parts of 

 them strike the country with westerly 

 winds which have also pushed the warm 

 water left by the dying-out current of the 

 Gulf Stream off Newfoundland across 

 the Atlantic, and raises the temperature 

 of the sea off Britain. 



When the cyclonic systems pass south 

 of England, as they occasionally do, 

 cold northeast and north winds are the 

 result, chilling the country despite the 

 warm water surrounding the islands. 



It only requires a rearrangement o£ 

 the direction of the main Atlantic cur- 



