236 Bureau of Farmers' Institutes. 



(c) Fertilizing Materials Containing Potash Compounds. 



The more common sources of potash compounds for use as fer- 

 tilizers, found in the market, are the following: Camallite, cot- 

 ton seed hull ashes, green sand marl, kainit, krugite, muriate of 

 potash, nitrate of potash, sulphate of potash, sulphate of potash and 

 magnesia, tobacco steins, wood ashes, etc. 



Wood ashes formerly constituted the main source of potash 

 compounds in our agriculture, aside from what was furnished by 

 farm manures. But for some years past the chief source of pot- 

 ash supply has been the different compounds obtained from the 

 German potash mines at Stassfurt in northern Germany. The 

 deposits are so extensive as to appear inexhaustible. 



Oarnallite is one of the products of the German potash mines. 

 It contains from. 20 to 22 per cent, of muriate of potash, equiva- 

 lent to 13 to 14 per cent, of actual potash, together with chloride 

 of magnesia and a very small amount of sulphate of potash and 

 magnesia. It is essentially a mixed chloride or muriate 'of potash 

 and magnesia. The material is generally purified and concen- 

 trated before reaching market. 



Kainit is the most common product of the German potash mines. 

 It is a mixture of several different compounds, containing 23 to 

 2G per cent, of sulphate of potash, equivalent to 12 to 14 per 

 cent, of actual potash, together with about 35 per cent, of com- 

 mon salt, some sulphate and chloride of magnesia and a small 

 amount of gypsum. 



Krugite is a low-grade potash compound obtained from the 

 German potash mines. It contains from 14 to 16 per cent, of 

 sulphate of potash, equivalent to 8 or 9 per cent, of actual potash, 

 together with considerable gypsum, sulphate of magnesia and 

 some salt. 



Muriate of Potash, also a product of the Stassfurt mines, is 

 the main source of supply of potash for commercial fertilizers in 

 our market. As taken from the mine it varies in purity, but is 

 purified and concentrated for market. The muriate of potash 

 most common in the market contains SO to 85 per cent, of this 

 product, which is equivalent to 50 to 53 per cent, of actual potash. 

 A still more concentrated form, containing 95 to 98 per cent, of 

 pure muriate, is sometimes found in the market. 



Sylvinit resembles kainit, containing about 15 to 16 per cent, 

 of actual potash in the form of both sulphate and chloride. It 



