486 



Trans. Acad. Sci. of St. Louis. 



was the only one available at either of the points at which the 

 work was done : — 



NaCl 3.03% 

 MgCIa .82 " 

 MgS04 .26 •' 

 CaS04 .16 " 

 , KCI .08 " 



(Residue — Si, P, CaCOa, etc.) 



From the above table it will be seen that sea water contains 



about 3.86 per cent of the various salts. Sodium chloride is 

 ten times as abundant as the magnesium chloride, and this in 

 turn four times a.s abundant as potassium chloride, whereas 

 the toxic value of the latter is considerably higher than either 

 of the former. With the exception of the magnesium sul- 



