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CHAPTER VIII. 



GYPSUM, NITRATE OF POTASH, AND AMMONIA. 



Gypsum allied to lime in its composition and general effects. 

 Preferable for green crops and grass-lands. Dr. Pinkers' 

 experiments. How Gypsum is applied. Its effects upon 

 leaves and stems. Highly appreciated in Europe. Aden 

 pumice. Mr. Smith's experiments on clover and wheat. 

 Mr. Robertson's experiments. Refuse of soda-water 

 manufactories. 



Nitrate of potash. Sora Khar. Mr. Robertson's experi- 

 ments. Consumption of nitrates steadily increasing. 

 Quantity per acre, and mode of application. Effect on the 

 plant. Common salt checks the tendency of saltpetre to 

 make the crop run into grass. Ammoniacal liquor of 

 gas-works. Its usefulness for kitchen plants, and mode of 

 application. 



GYPSUM, or native sulphate of lime, is closely 

 allied to lime in its effects, as also in its 

 general usefulness as a mineral manure. In 

 Germany it is applied, in the burnt and unburnt 

 state, to all kinds of grass and green fodder- 

 lands, but its use is now extending to all descrip- 

 tions of lands. In America it is used chiefly 

 for grain crops, and the results are said to be 

 extremely satisfactory. 



Gypsum is found in abundance all over India, 

 but I would recommend its use for the 



