A WONDERFUL WORLD 



Nitrogen is like a cold-blooded, lethargic person — 

 it combines with other substances very reluctantly 

 and with but little energy. Oxygen is just its op- 

 posite in this respect: it gives itself freely; it is "Hail, 

 fellow; well met!" with most substances, and it en- 

 ters into co-partnership with them on such a large 

 scale that it forms nearly one half of the material of 

 the earth's crust. This invisible gas, this breath of 

 air, through the magic of chemical combination, 

 forms nearly half the substance of the solid rocks. 

 Deprive it of its affinity for carbon, or substitute ni- 

 trogen or hydrogen in its place, and the air would 

 quickly suffocate us. That changing of the dark 

 venous blood in our lungs into the bright, red, ar- 

 terial blood would instantly cease. Fancy the sen- 

 sation of inhaling an odorless, non-poisonous atmos- 

 phere that would make one gasp for breath! We 

 should be quickly poisoned by the waste of our own 

 bodies. All things that live must have oxygen, and 

 all things that burn must have oxygen. Oxygen 

 does not burn, but it supports combustion. 



And herein is one of the mysteries of chemistry 

 again. This support which the oxygen gives is utterly 

 unlike any support we are acquainted with in the 

 world of mechanical forces. Oxygen supports com-, 

 bustion by combining chemically with carbon, and 

 the evolution of heat and light is the result. And 

 this is another mystery — this chemical union which 

 takes place in the ultimate particles of matter and 



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