CH. XXVII. NITROGEN, 235 



great all over Europe ; yet still he had not hit upon the 

 entire truth — he had given the facts, and it remained for 

 Lavoisier to read the riddle. 



Besides his chemical writings, Priestley published many 

 books on theology, and though he was a singularly gentle 

 quiet man, yet his religious and political essays were often 

 very severe, and they led to his being driven out of Bir- 

 mingham, and his house burnt by the mob, when they at- 

 tacked the leading Dissenters during the panic caused by 

 the French Revolution. After living for some time near 

 London he emigrated to America, where he died in 1804. 

 He continued his chemical experiments up to the time of 

 his death, and made many important discoveries, but the 

 chief discovery which will always be connected with his 

 name was that ^i oxygen , in 1774. 



Properties of Nitrogen determined by Dr. Rutherford 

 in 1772. — There now remains to be mentioned only one of 

 the four gases spoken of at page 226, namely, nitrogen. 

 This gas was first properly described by Dr. Rutherford in 

 1772, but there is very little to be said of it except that it 

 has scarcely any of those properties which belong to the 

 other gases. It does not support life or flame like oxygen ; 

 it does not make lime-water cloudy as carbonic acid does, 

 nor does it bum like hydrogen. In fact, it is a dull sleepy 

 gas, which remains after oxygen has been taken out of the 

 air, and which can be driven out of many solid bodies, 

 especially nitre or saltpetre. 



Lavoisier lays the Foundation of Modem Chemistry, 

 1778. — The determination of nitrogen completes the history 

 of the discovery of those gases of which fire, air, and water 

 are composed ; but you will have noticed that we have not 

 yet arrived at the new explanation of chemical changes which 



