198 



TRANSACTIONS OF THE ILLINOIS 



by whose intelligent application we can not only modify climate, but all 

 the operations of Nature. 



Light falls upon the ocean; since it can not perish what becomes of 

 it? A small poition is reflected, but since the bottom of the ocean is 

 dark, what is not reflected must pass into some other mode of force. We 

 know some of it passes into heat, by whose agency that immense amount 

 of water which falls in rain, is evaporated. Again, light falls on the land 

 surface of the earth. What becomes of it.'' A portion we know is 

 reflected, and another portion we know is transformed into heat. But 

 since earth currents are started under solar action, a portion of the light 

 must also be converted into electricity. The electricity of the earth being 

 negative as respects that of the air, it mounts the highest objects such as 

 hills, trees, and mountains^ so as to bring it in as close proximity as possi- 

 ble to the positive electricity of the air. The dry atmosphere being a 

 non-conductor, neither electricity can pass through (unless by disruptive dis- 

 charges), except by making a vehicle of matter for transporting it. Hence, 

 the positive electricity seizes upon the aqueous vapor over the ocean, and 

 the mutual elective attraction gives motion to the molecule of water thus 

 affected. Hence, it is drawn from over the ocean to the continents, 

 especially to the mountains, and is there condensed and precipitated as 

 rain. 



But once more : light falls upon vegetation. Here only a small por- 

 tion is converted into heat, 'because the foliage of all vegetation I'emains 

 cool. What becomes of the light in this case.? We know under its 

 influence, chemical action is started ; water and carbonic acid are decom- 

 posed, and under electric currents and magnetic force, the hydrogen and 

 carbon obtained is utilized in building up vegetable tissue, while the oxy- 

 gen is let free. Animals, in digesting vegetable tissue, develop again the 

 heat absorbed and fixed in growth. The conservation of force, by the 

 mutual convertibility of its forms, therefore, is an endless chain that runs 

 through and binds the physical universe together. 



Here, then, is the great law that we must make available in all our 

 dealings with Matter. By planting belts of timber, we not only apply the 

 principle of this law to sheltering ourselves and our flocks against the 

 rigors of winter, but we check the inroads of those arctic tempests, 

 ^vhose icy breath smites with paralysis and death our flocks, fields, and 

 orchards. 



Dr. Warder said that he had been unwilling to accept the proposi- 

 tion that the specific heat of trees was of much value in raising the 

 temperature of the atmosphere. Other well-known and often explained 

 causes, he thought sufficient to account for the modifying influences which 

 forests are known to exert. 



Mr. Douglass quoted Louden's assertion, that snow melted sooner on 

 Norway Spruce than on any other tree ; he also said that Mr. Meehan, 

 who is good American authorit}', insists that evergreen trees emit heat, 

 from the root upward, even when the earth is frozen solid around the 

 roots. He referred to the fact tliat hyacinths have been known to grow, 



