Kainite 



and is generally guaranteed at 12 -4 per cent. 

 Formerly it was considered that the potash it con- 

 tained was present under the form of sulphate. 

 This is not so. It is in the form of chlorure. 



Kainite contains about 35 per cent, common 

 salt (NaCl) ; about 30 per cent, salts of magnesia, 

 especially sulphate, but often also chlorure ; 12*5 

 per cent, water of crystallisation, and a small 

 quantity of impurities. 



Considerable quantities are sold annually under 

 the names of Kainite, Hartsalz, and Schoenite. In 

 1905 there was an output of nearly 2,500,000 metric 

 tons. 



Care must always be taken that the kainite does 

 not contain chlorure of magnesia, because that is 

 not only harmful to vegetation, but, being de- 

 liquescent, impairs the keeping qualities of the 

 manure. ^Vhen the kamite has become hardened 

 by storing, it is very difficult to apply, and the 

 lumps must first be crushed by means of a mattock 

 or spade, or, if large quantities are being employed, 

 by a grinding machine. 



Calcined kainite, from which the chlorure of 

 magnesia has been expelled by heat, can be bought, 

 and is to be preferred. Kainite is the potassic 

 manure in which the potash is the cheapest per unit 

 at the place of origin, but because of its evanes- 

 cence preference should be given to concentrated 

 chlorures of potash in places far from the source. 

 In the former case the cost of transport has to be 

 paid on substances which do not constitute manure. 



Kainite is very suitable for pastures, clover, beet- 

 root, com, etc. 



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