Nitrate of Potash (KNO,) 



Also it does not give potatoes the bad taste 

 which KCl gives. For these two crops one ought 

 always to have a guarantee that there is no chlorure 

 in the manure. 



In K2SO4 the unit of potash costs even more than 

 in KCl, because the latter is more easy to prepare, 

 and the former is in greater industrial demand. It 

 is the dearest of the potassic manures, nitrate of 

 potash [KNO3] being rarely employed. 



Being so dear, it is sometimes adulterated with 

 chlorure of sodium, sulphate of sodium, or crude 

 Stassfurt salts just like KCl. 



Its use is limited to tobacco and potatoes. 



Nitrate of Potash (KNO3). 



This is still called Nitre or Saltpetre. It is in 

 the form of white crystals and light prisms. 



It is very soluble in water and has a piquant 

 taste, and, if thro^^Tl on to a red-hot shovel, fuses 

 without lighting. 



It is found in certain parts of India, where it is 

 formed from organic matters in a soil rich in potash. 

 The product evidently is not pure. England has 

 dra\\Ti on the Indian supplies for a long time, but 

 now it is generally made by the reaction of chlorure 

 of potash on nitrate of soda. The unit of nitrogen 

 and of potash respectively will then be of superior 

 value to that of nitrate of soda and chlorure of 

 potash. Its general use is not justified on account 

 of its price. 



Formerly it was made in nitre beds. These were 

 layers of horse manure well aerated, and watered 

 with urine, in which wood ashes were mixed and the 



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