MANURES. 289 



Too heavy applications tend to the development of stem 

 and leaf at the expense of grain or root as the case may 

 be, and with the cereals may bring about "laying." 



In connection with the use of the manure it is to be 

 noted that it should never be allowed to lie mixed with 

 superphosphate for any length of time, as the latter always 

 contains free acid which decomposes the nitrate with 

 liberation of nitric acid. At ordinary temperatures 

 this loss may be practically nothing, but if, through any 

 cause, the temperature of the mass rises, the loss may 

 become very considerable. If nitrate is to be applied with 

 superphosphate it is therefore better to apply the manures 

 separately, or at any rate to mix them only immediately 

 before use. Again it is not advisable to allow nitrate 

 to lie in contact with any highly organic mass like farm- 

 yard manure, as under these conditions reduction of the 

 nitrate may take place with the escape of free nitrogen 

 to the air. 



The following facts are of interest in view of the place 

 nitrate of soda is now taking in Egyptian agriculture. 



In the year 1904 about 2500 tons were imported into 

 Egypt; in 1905 this increased to 5000 tons, in 1906 some 

 11,000 tons were imported and in 1907. 20,000. In 1904 

 the average price ] er ton was 1000 P.T.,in 1905 1025 P.T., 

 and in 1906 nearly 1,100 P.T. Up till 1905 practically all 

 the nitrate of soda imported was applied to the wheat and 

 cotton crops, wheat taking about 90 per cent, of the con- 

 sumption. In 1906 some 500 tons were applied to the 

 maize crop. 



