What 



Potash 



Does 



Nitrate 



of 



Potash 



Sources 



of 



Potash 



It is never found in nature pure, but invariably in com- 

 bination with some acid. One of its best known combinations 

 is with carbonic acid, forming carbonate of potash, which is 

 the common form in which we find it in ashes. It is the 

 carbonate of potash which is leached out of ashes and which 

 is used in the manufacture of soap. The exact form in 

 which the potash exists in plants is not well understood, but 

 it, in connection with silicic acid, is believed to aid in giving 

 the stiff quaUty to the stalk and also to the hull of the seed. 

 When a plant is burned, we always find potash in the ashes in 

 the form of carbonate. 



We also find it in nature in combination with nitric acid, 

 forming nitrate of potash — a chemical which enters largely 

 into the manufacture of gunpowder and is also used exten- 

 sively in brines for pickling meats. This form of potash can 

 be leached out of certain soils in which there is a large amount 

 of organic matter or out of horse manure. It also appears 

 in nature in the form of chloride of potash, which in chemical 

 composition is a salt similar to chloride of soda (common salt). 



The original and chief agricultural source of potash was 

 the ashes from burned wood, and in this form it exists largely 

 as carbonate and silicate of potash; but ashes afforded only 

 a small supply of potash, and it became necessary to find some 

 natural supply. This was found in Germany, so that today the 

 world turns to that country for its source of artificial potash. 

 The sources of potash, then, are the German potash salts, 

 nitrate of potash, and, finally, wood ashes, chiefly from Canada. 



Lime, Occasionally Needed 



Sour 

 Soils 



Lime has been used as a fertiUzer from time immemorial, 

 but in later years it has been neglected because it has been 

 overshadowed by the great trio, nitrogen, phosphoric acid and 

 potash, and because it has been assumed that most soils con- 

 tain enough available lime, which is no doubt true. Lime 

 is an important ingredient of all plant structures, and of 

 this, most soils have an abundant available supply. We have 

 learned, however, that while soils do contain an abundant supply 

 in available form, yet that it is necessary to apply it occasionally 

 in a caustic form to correct "soiu*" soils. 



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