COMPOSITIOX OF SEA WATER 



147 



From a total of yy very complete analyses of samples of ocean 

 water obtained by the Challenger Expedition, Dittmar (2: i8q, 204; 

 Krummel-20 : 2iq) has calculated the following average composi- 

 tion of the salt content of the sea. The calculations are in percent- 

 ages of the total solids, in grams per thousand grams of sea water 

 (permille) and in British tons per cubic mile of sea water. The 

 total of the solids is taken at 35 permille, or 3.5 per cent, by weight 

 of the sea water. The earliest calculations of Forchhammer (7), 



based on more than 150 analyses of sea water, gave : NaCl 78.32% 

 of the total solids, or a salinity of 26.862 permille; MgCL, 9.44%, 

 or 3.239 permille; MgSO^, 6.40%, or 2.196 permille ; CaSO^, 3.94%, 

 or 1.350 permille. The K is calculated as KCl, 1.69% of the 

 total solids, or a salinity of 0.582 permille, no KoSO^, MgBr, 

 or CaCOa being given. A residue of 0.21% or 0.070 permille 

 is left, making a total of 100% solids, or a salinity of 34.299 

 permille. 



Calculated in percentages of ions, we have (Tolman-39) : 



* One British ton equals 2,240 pounds avoirdupois; one metric ton equals 

 1,000 kilograms, or 2,204.6 pounds avoirdupois. One cubic mile of sea water 

 (density 1.026) weighs 4,315,000,000 tons. 



t Including all traces of other salts. 



