ON THE CONCENTRATION OF A SOLUTE. DAVIS. 299 



temperature gradient from top to bottom, according as the 

 solubility increases or decreases with temperature. 



If such a concentration gradient exists for the saturated 

 solution, there would still exist one, thought not the same in 

 magnitude in solutions not saturated. 



Taking the case where increase of temperature is followed 

 by increase of solubility as is the case of most salts in sea water, 

 and where the direction of the temperature gradient and of the 

 flow of heat is downward, as in the ocean, the concentration will 

 increase from the bottom upward. 



Now the temperature of the ocean decreases fairly rapidly 

 down to about 800 fathoms, from about 70 F. to 38 F., but 

 after that for the next 1,000 fathoms .or more it decreases only 

 1 to 2 F, so that the temperature of the ocean at great depths 

 is remarkably constant. See Challenger Reports, vol. 1, table 

 6, and also the report on deep-sea temperatures). 



800 



The effect of temperature will thus be a decrease in con- 

 centration with depth down to the point where the temperature 

 becomes fairly constant. After this the effect of temperature will 

 gradually die away. 



