- 125 1. 



Our atmosphere in repose presses with a force, of 

 16 Ib. to the square inch, If this atmosphere was com- 

 pounded exclusively of the four .gases, hydrogen, oxygen, 

 nitrogen and carbon, in the proportions which scientists 

 generally assume- viz. about 76/ of nitrogen, 16/ of 

 oxygen, 8% of hydrogen and lio of carbon these ele- 

 ments remaining in such proportions would not be subject 

 to any necessary disturbance or movement. Though in- 

 creased temperature in any place would expand the air r 

 arid the gases in obedience to natural law, being heated, 

 would rise, the expansion would act also in other direc- 

 tions and the pressure would remain unchanged; and if 

 under such conditions any wind current is conceivable, it 

 must be divided into strata, the upper driving from the 

 Equator to the Poles and the lower from the Poles to - 

 the Equator. In reality we observe almost the precise 

 antithesis. In summer southern winds prevail; in winter, 

 northern; while in general nothing is more uncertain than 

 the direction of the winds which gather and disperse the 

 clouds from and towards all quarters of the heavens. 

 What can be the cause of this? 



As I said before on the earth's surface there are two 

 heavy gases nitrogen and carbon, of which the first is 

 the constructive and the latter the nourishing element in 

 vegetation. 



Let us imagine a locality in which is growing a nor- 

 mal vegetation, surrounded by all the necessary condi- 

 tions for its well-being, a moist soil, adequate supplies 

 of nitrogen and carbon, by day cloudless sunshine, by 

 night clear moon-light. Under the daily action of the sun 

 the vegetable world around distils its oxygen, which,, 

 uniting with hydrogen, flies off to the sun. The greater 

 the force of sunshine the stronger the upward flood of 

 gas, and this strenuous element forcing its passage through 

 the atmospherical azote, expands and raises it. At this 

 time the moon, beginning to act by the force of its re- 

 flected electricity, comes to the sun's aid, and drawing 

 back the needed nitrogen restores sustenance to vegeta- 



