144 MANURES. VII. 



exhausted, it naturally occurs to one that a similar fate may 

 soon befall the supplies of nitrate. Various estimates of 

 the total available nitrate in the deposits of Chili, Peru, 

 and Bolivia have been made, ranging from 63,000.000 to 

 178,000,000 English tons. In 1895 the total export from 

 Chili reached 1,220,000 tons, while the following table gives 

 the world's consumption for the past years : 



1896. 1897. 1S98. 1899. 



Europe (continent)... 805,000 867,500 900,000 1,017,000 



United Kingdom ... 105,000 108,000 132,000 123,000 



United States ... 105,000 110,000 142,000 160,000 



Other countries 8,000 14,500 12,000 30,000 



Total ...1,023,000 1,100,000 1,186,000 1,330,000 



The average prices at Liverpool have been 

 7 15s. 5d. per ton in 1897. 

 7 11s. 3d. ,, 1898. 

 7 19s. 7d. 1899.- 



Ammonium Sulphate. When organic nitrogenous bodies 

 are submitted to destructive distillation, i.e., heated strongly 

 without access of air, the nitrogen which they contain is to a 

 great extent expelled as ammonia, which is carried away in 

 the vapours and gases simultaneously produced. The most 

 important operation of this kind is the distillation of coal, and 

 it is mainly from this source that the supplies of ammonium 

 compounds are obtained. Ordinary coal contains a little over 

 1 % of nitrogen, and when burnt in the usual way this nitrogen 

 escapes into the air, mainly in the free state. When coal is 

 distilled, however, a portion of the nitrogen is liberated as 

 ammonia and is found in the so-called " ammoniacal liquor" 

 which results from the cooling of the vapours evolved during 

 the distillation. Coal is distilled for the production of coal-gas 

 for illuminating purposes and also, in a somewhat different 

 manner, for the manufacture of the special coke used in iron 

 smelting. Gas works and coke ovens thus provide a large 

 share of the " ammoniacal liquor" which forms the raw 

 material for the manufacture of ammonium salts. A similar 



* Jour. Soc. Chem. Incl. 1900, 88. 



