46 



It is easy to observe the rapid consumption of oxygen 

 by combustion. Take a small piece of paper, twist it 

 into a tube and place it in the water, first setting light 

 to the edges: after this cover it with any large jar or 

 other such vessel. In one or two seconds you will see 

 that the oxygen under the jar has been exhausted, the 

 water has been drawn up inside and the fire, without burning 

 down, has gone out. Another still better experiment can be 

 conducted with a small wax candle-end fixed in a walnut. 

 The oxygen, in this case, is almost instantly exhausted. 



Imagine then the quantity of oxygen needed to supply 

 a fire spread over a hundred versts ! One can say, 

 without hesitation, that the whole atmosphere of the globe 

 would be consumed on a single prairie, or to speak 

 more precisely the 16 % of oxygen contained in it could 

 be so consumed. 



Our world is a gigantic solar laboratory. For every 

 sort of chemical combination on the earth or under it, 

 oxygen is needful, and we find in the vegetable out-put 

 of the earth's surface as it were a cosmic factory for the 

 production of this indispensable gas. And . yet without 

 hydrogen the spheres would seem like bodies without 

 arms. Other gases covering their surface would conduct 

 themselves quietly, rising and falling according to their 

 heat and nothing more. Hydrogen is the stirring ele- 

 ment in life itself, and uniting with oxygen, it throws 

 that gas upward to inconceivable altitudes, rushing with 

 it like a hurricane towards the sun-furnace, to surrender 

 its partner in space for consumptions in the flame, and 

 raising the sun storms to scatter forth on all sides the 

 vitalising solar rays, which in the form of warmth and 

 light flow back to earth and to the other planets to re- 

 new by fresh productive energies the same exchange, and 

 to reproduce again ozone. In a word we may call hy- 

 drogen the mediator which unites the interests of the 

 central sun and the surrounding planets. 



The expansive force of hydrogen is well-known also, 

 upon earth. All explosives, as, for instance, nitro-gly- 



