124 OF THE INORGANIC CONSTITUENTS OF PLANTS. 



and every breeze must carry this away. Now, as 

 thousands of tons of sea-water annually evaporate 

 into the atmosphere, a corresponding quantity of the 

 salts dissolved in it, viz. of common salt, chloride 

 of potassium, magnesia, and the remaining constitu- 

 ents of the sea-water, will be conveyed by wind to 

 the land. 



This volatilization is a source of considerable loss 

 in salt-works, especially where the proportion of 

 salt in the water is not large. This has been com- 

 pletely proved at the salt-works of Nauheim, by the 

 very intelligent director of that establishment, M. 

 Wilhelmi. He hung a plate of glass between two 

 evaporating houses, which were about 1200 paces 

 distant from each other, and found in the morning, 

 after the drying of the dew, that the glass was 

 covered with crystals of salt on one or the other 

 side, according to the direction of the wind. 



By the continual evaporation of the sea, its salts * 

 are spread over the whole surface of the earth ; and 

 being subsequently carried down by the rain, furnish 



* Analyses of sea- water. 



Of the British Channel. Of the Mediterranean. 



— Schweitzer. — Laurens. 

 In 1000 parts. — Marcet. Grs. Grs. 



Water 964.74372 959.26 



Chloride of Sodium 26.660 27.05948 27.22 



" of Potassium 1.232 0.76552 0.01 



" of Magnesium 5.152 3.66658 6.14 



Bromide of Do. 0.02929 



Sulphate of Soda 4.660 



» of Lime 1.5 1.40662 0.15 



" of Magnesia 2.29578 7.02 



Carbonate of Lime 0.03301 5 ^^'^' ^^"'^ ^"^ I 0.20 



^ magnesia. 5 



According to M*Clemm, the water of the North Sea contains in 1000 



parts, 



24.84 Chloride of Sodium. 



2.42 Chloride of Magnesium. 



2.06 Sulphate of Magnesia. 



1.35 Chloride of Potassium. 



1.20 Sulphate of Lime. 

 In addition to these constituents, it also contains inappreciable quan- 

 tities of carbonate of lime, magnesia, iron, manganese, phosphate of 

 lime, iodides and bromides, silica, sulphuretted hydrogen, and organic 

 matter, together with ammonia and carbonic acid. (Liebig's Annaltn 

 der Chemie, Bd. xxxvii. s. 3.) 



