CHAPTER X. 



Experiments with the carbonates, phosphates, and silicates of potash and soda. 

 Composition of the carbonates of potash and soda, their properties and their 

 functions in the soil and in the plant. Eesults of published experiments with 

 these carbonates. Suggestions for experiments with the carbonates of potash 

 and soda. Composition of the phosphates of potash and soda. Results of 

 experiments with the phosphate of soda. Suggestions for comparative ex- 

 periments with these phosphates applied alone. Composition of the silicates 

 of potash and soda, their properties and their functions in the soil, and in the 

 plant. Results of past experiments with these silicates. Suggestions for 

 future experiments with the silicates of potash and soda. 



1. Composition of the carbonates of potash and soda, their 

 properties and their functions in the soil and in the plant. 



1. COMPOSITION of the carbonates of potash and soda. 



Carbonate of potash, \ '( Potash, 68.2 



(dry pearl ash,) J C< >r \ Carbonic acid, 31.8 



100 



Carbonate of soda (crystallised, I , ' . . , 



or common soda of the shops,)' } * ts of j $* d > * 



100 



Carbonate of soda (dry ) . ( Soda, 58.7 



or pure soda ash,) J c< }I \ Carbonic acid, 41.3 



100 



2. Properties of these carbonates. 



a The carbonate of potash, or pearl ash, attracts moisture 

 rapidly from the air, and deliquesces or runs to a liquid. It has 

 an acrid, alkaline taste, and dissolves in less than its own weight 

 of water at 60 F. 



