AMMONIA. 195 



CLASS IV. 



ALKALINE MINERALS. 



The minerals of this class contain one or more of the common alkalies, Ammonia, Potash 

 or Soda, usually combined with an acid. 



ORDER I. AMMONIA. 



1. Carbonate of Ammonia. 



CARBONATE OF AMMONIA. 



The carbonate of ammonia has been detected in the water of a spring in the city of New- 

 York, which was analyzed many years since by the late Mr. George Chilton.* Its occurrence, 

 although rare, is not entirely new, as it has been found by Professor Fischer in the thermal 

 water of Warmbrunn in Silesia ; by Wetzler, in the cold spring of Krumbach in Bavaria ; 

 and by Kastner, in that of Kissingen, in the same kingdom.! Dr. Daubeny supposes that it 

 may be of still more frequent occurrence, and that chemists have perhaps overlooked its pre- 

 sence, in consequence of having driven it off by the heat, which, in analyzing the water, they 

 had in the first instance applied. 



Carbonate of ammonia is also occasionally found in rain water, as has recently been shown 

 by Liebig and others ; the anmionia being formed by the decomposition of various animal and 

 vegetable matters, taken into the atmosphere, combined with the carbonic acid which there 

 exists, and finally brought down by rain and snow. 



The presence of this salt may be determined by the effervescence which is produced when 

 it is treated with sulphuric acid, and by the strong ammoniacal odour which is evolved when 

 it is mixed in a mortar with pure potash or quicklime. 



* American Journal of Science, XVIII. 346. t Daubeny. Report on Mineral and Thermal Watert 



