82 THE OCEAN 



coincides with the path of least barometric 

 pressure in that region, the position of which 

 gives to the North and South Atlantic their 

 distinctive contrasted features. 



The distribution of temperature in the 

 Pacific at a depth of 100 fathoms is precisely 

 the reverse of what obtains in the Atlantic, 

 the South Pacific being much warmer than 

 the North Pacific. In the North Pacific the 

 highest temperature (70° F.) is restricted to 

 two very small areas, whereas in the South 

 Pacific the area with a temperature over 70° F. 

 is large, and encloses another extensive area 

 where the temperature exceeds 72° F. This is 

 due to the fact that the line of lowest baro- 

 metric pressure lies to the south of the equator 

 from long. 160° E. to 130° W. For eight 

 months of the year this state of things sub- 

 stantially holds good, culminating in Decem- 

 ber, January, and February, when barometric 

 pressure is very low in Australia, and when 

 the north-east trades and ocean currents 

 of the western Pacific extend into the South 

 Pacific to about lat. 15° S. 



A feature of the temperature at 100 fathoms 

 in all the oceans is a pronounced increase in 

 the eastern equatorial region of each ocean on 

 nearing the continents : thus, in the Pacific 

 about the Galapagos Islands, the temperature 

 is 62° F., or twelve degrees higher than in the 



