222 



DEPTHS OF THE OCEAN 



were not sufficiently accurate. More recently several indica- 

 tions of a rise of temperature towards the bottom have been 

 observed. The pressure and the internal heat having the 

 same effect, it is difficult — at our present stage — to determine 

 how much is due to the internal heat of the earth. In any case 

 the bottom-water temperatures would be considerably lower but 

 for the effect of pressure on the sinking waters. 



It may be stated as a general rule that the temperature of 



Fig. 157. — The distribution of Temperature at four different Stations 



IN THE Summer of 1910. 



The positions of the Stations are shown in the small inset map. 



ocean water is in summer highest at the surface, and decreases 

 gradually towards the bottom. Fig. 157 shows the distribution 

 of temperature as observed at four stations during the " Michael 

 Sars " Atlantic Expedition, the position of the stations being 

 indicated on the little inset map. Station 64 is situated in the 

 Sargasso Sea westward of the Azores, Station 87 in mid-ocean 

 between France and Newfoundland, Station 10 1 between 

 Scotland and Rockall, and Station 106 in the Faroe-Shetland 

 Channel north of the Wyville Thomson Ridge. Station 106 

 belongs to the region of the Norwegian Sea, whereas the other 



