52 IIOAV CROPS FEED. 



of ammonia, which copiously escapes in the form of car- 

 bonate, and may be separated by distillation. 



When bones are heated in close vessels, as in the manu- 

 facture of bone-black or bone-char for sugar refining, the 

 liquid product of the distillation is strongly charged with 

 carbonate of ammonia. 



Commercial ammonia is mostly derived, at present, from 

 the distillation of bituminous coal, and is a bye-product of 

 the manufacture of illuminating gas. The gases and va- 

 pors that issue from the gas-retort in which the coal is heat- 

 ed to redness, are washed by }>assing tlirough water. Tliis 

 wash water is always found to contain a small quantity of 

 ammonia, which may be cheaply utilized 



The exhalations of volcanoes and fumeroles likewise 

 contain ammonia, which is probably formed in a similar 

 manner. 



In the processes of combustion and decay the elements 

 of the organic matters are thrown into new groupings, 

 which are mostly simpler in composition than the original 

 substances. A portion of nitrogen and a corresponding 

 portion of hydrogen then associate themselves to form am- 

 monia. 



Ammonia is a Stroni? Alkaline Base.— Those bases 

 which have in general the strongest affinity for acids, are 

 potash, soda, and ammonia. These bodies are very similar 

 in many of their most obvious char.icters, and are collec- 

 tively denominated the alkalies. They are alike freely 

 soluble in water, have a bitter, burning taste, alike corrode 

 the skin and blister the tongue ; and, united with acids, 

 form the most permanent saline compounds, or salts. 



Carbonate of Ammonia. — If a bottle be filled with car. 

 bonie acid, (by holding it inverted over a candle until the 

 latter becomes extinguished when passed a little way into 

 the bottle,) and its mouth be applied to that of a vessel 

 containing ammonia gas, the two invisible airs at once 



