S9 



NITROGEN. 



Nitrogen gas is so called, because its base' 

 forms nitric acid by its union with oxygen. It was 

 by Lavoisier named azotic gas, and its base azote, 

 from a Greek word signifying without life, because 

 it is entirely destructive to animal life. 



This, also, though a very abundant principle, 

 cannot be exhibited in a free or uncombined state. 



In the state of gas, it forms a considerable part 

 of our atmosphere ; - in the solid state it enters into 

 the composition of animal and vegetable bodies, 

 nitric acid, and ammonia. It is incapable of sup- 

 porting combustion or animal life. It is not ab- 

 sorbed by water, and it has no acid properties. 



It may be obtained by separating the oxygen 

 from a portion of the atmospheric air ; the residue 

 will be nitrogen. This is done by exposing a cer- 

 tain quantity of atmospheric air to sulphuret of 

 potass, which absorbs the oxygen, leaving the 

 nitrogen free. 



It may be also obtained by treating muscular 

 flesh, (as lean veal) with nitrous acid in a retort ; the 

 flesh is decomposed, and the nitrogen set at liberty. 



That it does not maintain combustion, and is fatal 

 to animal life, may be proved by plunging a lighted 

 taper into a vessel filled with this gas, the taper will 

 be immediately extinguished. If a small animal, 

 as a mouse, or a bird, be immersed in it, it im- 

 mediately dies. 



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