The principle of constant ratios between the salts in ocean water unaffected by land drainage was laid down by Forchhammer in 1864, and firmly established by Dittmar (1884) . Dittmar's examination of 77 samples, collected from all the oceans of the world by H .M.S. Challenger in 1873-76, was so comprehensive, and his results so consistent, that some of his values are used to this day.
Lyman, John, and Richard H. Fleming. 1940. "Composition of sea water." Journal of Marine Research 3, (2). https://elischolar.library.yale.edu/journal_of_marine_research/566