78 HAPPY INDIA 



superphosphates. It does not produce such imme- 

 diate results, but its effect will be more lasting. 

 Various salts of potassium are found as minerals, 

 and in Europe it is common to give these to the 

 lands where there is a deficiency of potash. 



Unless the soil possesses every necessary constituent 

 the crops will be poor. If there is not sufficient 

 potash, the crops will be poor, though everything 

 else is abundant ; if there is not sufficient phosphoric 

 acid, the crops will be poor, though everything else 

 is abundant ; if there is not sufficient nitrogen, the 

 crops will be poor, though everything else abounds. 

 So that the success or failure of any special manure 

 cannot be judged simply by a trial to see whether 

 or not the crops have greatly improved by it, because 

 it may fail to give good results, not through a 

 deficiency in itself, but because some other manure 

 is required as well. 



Therefore for scientific agriculture it is necessary 

 to analyse the soil to ascertain whether there is 

 sufficient of each kind of manure, and what kind 

 is deficient, if any, and then it is only necessary to 

 add that ingredient which is wanting. 



In 1912, Mr. John Kenny, Instructor of Agriculture 

 to the Nizam of Hyderabad, published a valuable 

 book entitled Intensive Farming in India. On 

 page 133 he gives the result of manure on the produc- 

 tion of grain, as shown by experiments at the 

 Burdwan Government Farm. When the land was 

 not manured the output of grain per acre was 1,374 

 lb., and of straw 2,174 Ib. When 100 maunds 



