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MANUAL OF MODEKN VITICULTURE. 



In the following table we give an idea of the way of 

 establishing formulae for chemical manures. They may vary 

 greatly as far as substances are concerned, but they must all 

 represent the same weight of elements : 



Superphosphate of lime should be applied at the beginning 

 of winter, and well mixed with the soil ; nitrate of soda and 

 sulphate of potash should only be applied in spring. 



Other compositions are possible according to the cheapest 

 way matters can be purchased. Nitrogen may be derived 

 from sulphate and nitrate of ammonia, or nitrates of potash 

 or soda* Phosphoric acid may be derived from mineral 

 phosphates, star phosphates, bones, animal black, and 

 superphosphates. Finally, potash is to be found in alkaline 

 salts, sulphate of potash, potassium chloride, potassium 

 sulphide, nitrate or carbonate of potash, &c. 



Although cost is the main item in purchasing manures, 

 we must not forget that some act better than others in 

 certain soils. Potassium chloride and sulphide, and sulphate 

 of potash, for instance, seem to give better results than other 



* Nitrogen, in the form of nitrates, seems to promote a greater production of sugar in 

 must than when in the form of organic matters. 



