174 TRANSACTIONS OF THE ILLINOIS 



The English destroyed the forests of the Deccan, once of equable cli- 

 mate and exuberant fertility, until it now has become arid and sterile. 

 For several years the East India Company have been replanting large dis- 

 tricts with forests, in hopes of restoring its former climate. 



In Qiieensland, Australia, aridity has so much increased by the indis- 

 criminate destruction of the forests that the Australian government has 

 taken the care of forests in charge, and is annually replanting the 

 denuded districts. If anything further were necessary to prove the dele- 

 terious effects of denuding the earth of vegetation, we might quote the 

 highest scientific authorities, who, from facts that have fallen under 

 their observation, have given it as their unqualified opinion that defor- 

 estation can not be carried on anvwhere without degradation of climate 

 following as an inevitable consequence. These are the well-known opin- 

 ions, as expressed in their works on physical science, of Humboldt, Her- 

 schel, Boussingault, Marsh, and others. But we prefer to let facts speak; 

 they are of higher than human authority. 



We must now close the argument on this part of the subject, and 

 proceed to discuss another and perhaps the conti"olling law of Meteor- 

 ology, namely; that of electric tiction. Electricity is of two kinds : the pos- 

 itive and negative; or as it has been most pointedly yet typically expressed 

 in the Zend Avesta, the sacred book of the Parsees : " There are two 

 principles in nature : the male and female. In consequence of being of 

 opposite sexes they are perpetually seeking each other." Positive elec- 

 tricity (the male) fills interstellar space and penetrates somewhat into the 

 upper regions of our atmosphere. Negative electricity (the female) sur- 

 rounds and fills the Earth and all matter and bodies in space. Now if 

 an insulated conductor be charged with either positive or negative elec- 

 tricity, and brought in the vicinity of another but uncharged conductor, 

 by induction it separates the insensible electricities of the latter, attract- 

 ing the disgfcnilarto the nearer side, and repelling the similar electricity to 

 the farther side. Electric attraction, therefore, only subsists between the 

 opposite electricities. If a conductor is connigated, the ridges will show 

 greater electric tension than the furrows; in fact the latter maybe devoid 

 of any sensible electric excitement. The earth is a corrugated conduc- 

 tor; hence the negative electricity with which it is charged mounts to 

 the highest points, and therefore mountains are inore highly charged than 

 plains. The positive stoops down to meet the negative, but is prevented 

 by the intervention of the atmosphere, a non-conductor. Their meeting 

 is, therefore, only possible by the happening of either of two contingencies ; 

 first, when the mutual attraction is so great as to cause a disruption of the 

 intervening non-conductor, then thunder and lightning take place; or, 

 secondly, when the positive seizes upon some matter floating in the 

 atmosphere, as vapor or clouds, which give it transportation to its mate, 

 the mutual attraction giving the motion. This is the reason why clouds 

 dash themselves with such headlong fury against mountains. It also 

 shows why mountains are the recipients of greater quantities of rain than 

 plains. 



In the West, it is a well known fact that rains gather over and follow 



