SECTION III.— FERTILISERS AND 

 MANURES 



CHAPTER X 

 Artificial Nitrogenous Manures 



Sulphate of Ammonia. 



Ammonium sulphate is obtained from the ammoniacal liquor 

 obtained during the distillation of coal. The ammonia liquor is 

 either saturated direct with sulphuric acid, or else it is distilled 

 with lime and the gaseous ammonia collected in sulphuric acid. 

 The latter method yields the ordinary pure sulphate of ammonia 

 of commerce, direct saturation giving a very inferior product con- 

 taining sulphides, thiocyanates, and other injurious substances. 



Sulphate of ammonia should be 95 per cent, purity, and 

 normally contains 24-5 per cent, ammonia or 20*2 per cent, 

 nitrogen. 



89. Ammoniacal Liquor. 



(a) Qualitative Examination. — The ammonia liquor 

 may be examined qualitatively as follows : — 



Sulphides . . HgS formed on addition of 



acids. 

 Thiosulphates . S precipitated on addition of 



acids. 

 Carbonates . . COg formed on addition of 



acids. 

 Sulphates . . Test with barium chloride. 



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