440 Action of the Atmosphere upon newly -deepened SoiL 



100 of Water at 60» 

 dissolve 



Sodium, chloride 37-000 



Soda, nitrate 43-600 



„ sulphate 83-600 



„ carbonate 20-500 



„ bicarbonate 8*700 



,, phosphate 24' 700 



Lime, suli^hate 0-217 



Magnesia 0-019 



sulphate 114-000 



Iron, protosulphate 70-000 



Lime, carbonate 0-009 



„ hydrate 0-128 



Water combines with anhydrous bases, forming hydrates of 

 these bases, of which slaked lime is a familiar example, being a 

 hydrate of lime ; it also forms hydrates of neutral salts. Again, 

 it combines with both hydrated and anhydrous salts in the form^ 

 of what is called water of crystallization, as is instanced in the 

 family of minerals named zeolites. It also unites with dry acids 

 to form hydrated acids ; indeed some of these bodies without that 

 water seem to want their acid property, e. g. dry sulphuric acid. 



Rain-Avater, being derived by the action of evaporation and 

 wind from the sea, probably often contains traces of all the 

 matters found to compose the water of the ocean ; it may there- 

 fore be the means of conveying a very sensible amount of many 

 salts to the soil. The following analysis by Schweitzer will 

 show the composition of the waters of the English Channel, and 

 is contrasted with another of the waters of the Dead Sea by a 

 pupil of Dr. R. D. Thomson : — 



I have little doubt therefore that minute quantities of many 

 of these important salts are conveyed to the soil through the 

 medium of rain ; take for instance the first of the list, the chloride 

 of sodium : at Penicuik, according to Dr. Madden, the rain tliat 

 falls is said to contain so much common salt as alone to convey 



