CHAPTER XII. 



Experiments with the salts of ammonia. Composition of caustic ammonia, and 

 of the carbonate, sulphate, muriate, phosphate, nitrate, acetate, oxalate, and 

 humate of ammonia. Functions performed by the salts of ammonia in the 

 soil and in the plant. Results of experiments with carbonate of ammonia 

 and with ammoniacal liquor. Results of. experiments with sulphate of am- 

 monia. Results of experiments with muriate of ammonia (sal-ammoniac.) 

 Results of comparative experiments with the different salts of ammonia, and 

 with the nitrates of potash and soda. 



Ammonia and its salts are now recognised to be very gene- 

 rally useful in promoting vegetable growth. They impart to 

 plants a beautiful green colour ; increase the rapidity, and pro- 

 long the duration of their growth ; make them more succulent 

 and grateful to cattle ; and, for the most part, add to the bulk 

 and weight of the crop. In regard to them, three points 

 require to be investigated by experiment, -first, their special 

 effect upon particular crops in different soils and circumstances ; 

 second, their comparative effects ; and third, their comparative 

 economy to the practical fanner. 



1. Composition of caustic ammonia, and of the carbonate, sul- 

 phate, muriate, phosphate, nitrate, acetate, oxalate, and humate 

 of ammonia. 



Ammonia or caustic ammonia is a kind of air or gas which 

 is readily prepared by mixing together quicklime and sal-am- 

 moniac, each in the state of fine powder. It is colourless, but 

 has the strong pungent odour familiarly known in hartshorn and 

 smelling-salts. Its presence is readily detected, not only by its 

 smell, but by the white fumes it produces when a feather, 

 dipped in muriatic acid or in strong vinegar, is brought near to 

 the place where its presence is suspected. It consists of 



Nitrogen, 82-35 



Hydrogen, 17*65 



100 



