OCEANOGRAPHY 



435 



difference of two or three tenths of a degree. In these deeper 

 parts of the ocean the conditions are probably very similar; we 

 have there no variations worth mentioning, because the warming 

 of the surface and sub-surface waters by the sun has no effect 

 there, unless, indeed, the currents at these depths may vary so 



Fig. 14. — Temperatubes at One op the "Fham's" and One op the 

 "Valdivia's" Stations, in the Benguela Current. 



much that there may be a warm current one year and a cold one 

 another year. But this is improbable out in the middle of the 

 ocean. 



In the neighbourhood of the African coast, on the other hand, it 

 looks as if there may be considerable variations even in the deeper 

 zones below 500 metres (272 fathoms). During the Valdivia 



