Sea-Water.-Sea-water varies considerably in composition, being, of course, more concentrated, as a rule, in the tropical regions, where evaporation is most active, such, for example, as in the Mediterranean Sea and the Atlantic Ocean near the equator. According to analysis, the water in the English Channel contains in 1000 parts‑

Chloride of Sodium 28.05

Chloride of Magnesium…………………….. 3.66

Sulphate of Magnesia 2.29

Sulphate of Lime ……………………………. 1.40

Other Saline Materials ……………………….. .76

Total Solid Matter…………………….. 36. 16

Besides these, and perhaps contributing largely to the healthful qualities of sea-water, there exist in the ocean small quantities of iodine and bromide, and extremely minute amounts of some of the common metals. It has been found that, by dissolving a little common salt and carbonate of soda, lime and magnesia in distilled sea-water, its taste is rendered much more agreeable; and this plan, it is said, is adopted in the Russian navy.

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As in the last section where they talk about distilling sea water for drinking on ships, this talks about some of the other materials that can be extracted during the distillation process.  With the exception of salt extraction some of these other materials don’t seem terribly practical.  Times do change however, and if water is extracted every bit of material that comes with it has to go somewhere whether it can be sold in bulk for mass production of vitamins or horse supplements or what ever.