138 



HYDROGRAPHY. 





implies that this latter is moving as a body in a southerly direction and constitu- 

 ting the East Icelandic Polar Current. Still it is to be observed that what has been said here, does 

 not claim to be a perfect proof of the correctness of this conception, as the curves of salinity are 

 not determined with any great exactness. 



If the salt Atlantic-water could freeze when it is cooled in northern latitudes, the result of this 

 process would be that — in consequence of this formation of ice — salt water would be formed, which 

 had a still higher degree of salinity than that of the Atlantic. The extremely saliferous water would 

 on account of its high specific gravity sink to the bottom, and it is perhaps in this manner that the 

 deepest lying strata of the under-layer have been formed. 



According to the theory set forth by Professor Pettersson (1. c. or <Grunddagen af Skageracks 

 och Kattegats Hydrografb af Otto Pettersson og Gustaf Ekman page 121), the freezing point of water 

 is found at that temperature, at which the water has its greatest density, provided the salinity be 

 23 — 24 %» As to water of a higher degree of salinity, the temperature of the maximum density is 

 lower than that of the freezing-point According to this, water of this kind should not be able to 

 freeze by cooling from above, before the whole body of water had got the temperature of the 

 freezing-point 



