Vol. 4] 



Holway.—Cold Water Belt. 



283 



off Lower California is found in the northwest flowing warm 

 Mexican current previously mentioned. This current, accord- 

 ing to the charts of the Deutsche Seewarte, is more saline and 

 hence will sink and mingle with the colder water from the north- 

 ward. 



Another interesting area of cold water on the ocean bottom 

 is found off Japan in the great Tuscarora Deep. The source of 

 this cold water is doubtless the cold polar current coming down 

 by Kamchatka. The southern part of this cold water area has 

 an extension off to the eastward. It has a direction that appears 

 to be the resultant of a conflict between the deep part of the 

 north-flowing Japan stream and the cold water of the Kamchatka 

 current. Here again the idea of great depth of drift would 

 account for the fact that we have represented a stationary body 

 of cold water resting on the sloping ocean bottom. 



Of course, the hypothesis that these ocean currents and 

 drifts have a uniform direction to the bottom of the sea needs 

 additional evidence in its support. Meanwhile it offers a reason- 

 able explanation of the cold coast water on the North American 

 shore and of several peculiarities of the masses of very cold 

 water on the bottom of the North Pacific with little indirect op- 

 position to the hypothesis. 



The presence of the large area of cold water on the bottom 

 of the south central portion of the North Pacific here challenges 

 attention. Can it be accounted for by the known direction of 

 surface or bottom drift? It must have some connection with 

 the cold water of high latitudes to maintain its low temperature 

 of 35° or under. There is no evidence to connect it with the 

 cold water off North America. From its position in ecjuatorial 

 regions it must necessarily be supplied by subsurface currents. 

 There are few charts showing temperature below the surface in 

 the North Pacific. Turning to one by Makaroff* for the level 

 400 meters (218 Fm.) below the surface, the isotherms are found 

 to make a sharp bend to the southeast as may be seen in PI. 37. 

 This indicates a southeast flowing portion of the cold Kamchatka 

 current which has underrun the warm Japan stream. The 



* Makaroff , S. Le Vitiaz et L 'Ocean Pacifique. 



