200 THE CHEMISTRY OF CREATION. 



electricity, which acts in various- ways an 

 important part toward both organic life and 

 inorganic matter. The whole vegetable and 

 animal world are largely influenced by this 

 electricity, and it is doubtless intimately con- 

 nected with their life and well-being. It is 

 also greatly concerned in the formation of 

 clouds, rain, and similar phenomena. When 

 developed in intensity, as in the explosions 

 accompanying tempests, it effects various che- 

 mical decompositions in matters present in 

 the air. It has been considered that ammonia 

 may sometimes be produced by its influence. 

 It also occasionally produces small portions of 

 nitric acid. A peculiar ingredient, called 

 Ozone, is constantly produced by it. Its ser- 

 vices are very variable. Friction of currents of 

 air against each other, evaporation and chemi- 

 cal decompositions taking place on the earth's 

 surface, all produce it. It is generally, when 

 the air is clear, of the positive kind. This varies, 

 however, with the variations in its sources. The 

 earth, on the contrary, is always charged with 

 negative electricity. 



With these remarks on the physical constitu- 

 tion of the atmosphere and its connected pheno- 

 mena, we may pass on to what is more peculiarly 

 our province, and speak next of the Chemistry of 

 the Air. 



