OF ARTIFICIAL MANURES. 



169 



(1.) nitrogen, (2.) organic substances, (3.) salts of pot- 

 ash, (4.) salts of soda, (5.) phosphate of lime, (6.) gyp- 

 sum, (7.) carbonate of lime (in connection with mag- 

 nesia) ? 2d. In what combination is the nitrogen 

 principally present ? as an ammoniacal salt ? as a ni- 

 tric acid salt ? as an organic substance of easy or of 

 difficult decay ? By the reply to the first inquiry he 

 is placed in a position to calculate the approximate 

 value in money of the manure in question, whilst 

 from the subsequent answers he acquires tolerably 

 certain information as to the slow or rapid action 

 tbat may be anticipated from its use. Having ob- 

 tained the analysis, he can then compute, with the aid 

 of the preceding valuations, the price to be attached 

 to each separate substance, and add together the 

 single sums he has previously obtained. 



The following examples may contribute to greater 

 perspicuity, and also serve for a comparison of the 

 present market value of the better-known artificial 

 manuring agents with their value as ascertained by 

 this method. 



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