CARBONATE OF AMMONIA IN l.?'NF. 131 



superphosphate of lime, are substances of a very low price ; and 

 if they were added to urine until the latter lost its alkalinity, the 

 ammonia would be converted into salts, which would have r.o 

 further tendency to volatilize. 



When a basin, filled with concentrated muriatic acid, is placed 

 in a common necessary, so that its surface is in free communica- 

 tion with the vapors issuing from below, it becomes filled after a 

 few days with crystals of muriate of ammonia. The ammonia, 

 the presence of which the organs of smell amply testify, combines 

 with the muriatic acid and loses entirely its volatility, and thick 

 clouds or fumes of the salt newly. formed hang over the basin. In 

 stables, the same may be seen. The ammonia escaping in this 

 manner is not only lost, as far as our vegetation is concerned, but 

 it works also a slow, though not less certain, destruction of the 

 walls of the building. For, when in contact with the lime of the 

 mortar, it is converted into nitric acid, which dissolves gradually 

 the lime. The injury thus done to a building by the forrnaticr 

 of soluble nitrates, has received (in Germany) a special name • 

 salpeterfrass (production of soluble nitrate of lime). 



The ammonia emitted from stables and necessaries is alway-s 

 in combination with carbonic acid. Carbonate of ammonia and 

 sulphate of lime (gypsum) cannot be brought together at common 

 temperatures, without mutual decomposition. The ammonia 

 enters into combination with the sulphuric acid, and the carbonic 

 acid with the lime, forming compounds destitute of volatility, and 

 consequently of smell. Now, if we strew the floors of our stables, 

 from time to time, with common gypsum, they will lose all their 

 ofFensive smell, and none of the ammonia can be lost, but v. ill be 

 retained in a condition serviceable as manure (Mohr). 



With the exception of urea, uric acid contains more nitrogen 

 than any other substance generated by the living organism ; it is 

 soluble in water, and can be thus absorbed by the roots of plants, 

 and its nitrogen will be assimilated in the form of ammonia from 

 the oxalate, hydrocyanate, or carbonate of ammonia. It would 

 be extremely interesting to study the transformations which uric 

 acid suffers in a living plant. For the purpose of experiment, 

 the plant should be made to grow in charcoal powder. previously 

 beated to redness, and then mixed with pure uric acid. The ex- 



