STATE HORTICULTURAL SOCIETY. 173 



having been suirounded by water. Humboldt attributed this diminution 

 ot" the waters to the extensive clearings made in the valley. The elevation 

 of the valley and its immense fertility, had adapted its soil and climate to 

 the production of the cereals and fruits of Europe. Consecjuently it had 

 become almost as densely populated as the valley of the Rhine. When 

 the Revolution broke out, the peaceful valley of Aragua became the 

 theater of many bloody conflicts. At the first cry of independence, both 

 master and slave (the latter being freed) enlisted under the banners of the 

 Republic. Again and again its population was decimated until exter- 

 mination was accomplished. Plantations being abandoned, the recupe- 

 rative energies of nature in that tropical clime soon restored the forests. 

 Boussingault, who afterwards visited the valley, in his Eco7iomic Rurale 

 says : 



" Twenty-two years later I explored this valley. For many years pre- 

 vious the inhabitants had discovered that the waters of the lake were no 

 longer retiring, but on the contrary were rising. Grounds not long before 

 occupied as plantations were submerged. The island of Nuevas Apare- 

 cidas, which appeared above the surface in 1766, was again covered with 

 water, and Cabiera had again become an island. 



Clave, in his " Studies Upon Forest Economies," says : " St. Helena, 

 stripped of its ancient forests has become almost sterile from the failure 

 of rains. Within the last thirty years the wooded surface of the island 

 has been considerably extended by replanting, and the rain has increased 

 in proportion. The quantit} now falling is fully double what it was during 

 the imprisonment there of Napoleon." 



Wolf Spring, in the commune of Souby, ninety years ago, had no 

 existence. Only after long rains, water temporarily oozed from the soil 

 where the spring afterwards appeared. The spot is in the middle of a 

 steep pasture. About that time the owner perceived younpj firs spring- 

 ing up on theheights, which under protection soon became P dense grove. 

 When the trees were fully grown a fine spring appeared in the place of 

 the temporary ooze, furnishing an abundant supply of water, even 

 during the longest drouths, for fifty years. Twenty years since, the grove 

 was felled, and to-day the spring is as dry as it \vas ninety years ago. 



Mehemet Ali, the Viceroy of Egypt, fifty years since, planted some 

 forty or fifty millions of trees in Egypt to increase the rains. During the 

 time that the French under Napoleon occupied Egpvt (which was six- 

 teen months), not a drop of rain fell there. Since the trees planted by 

 the Viceroy have become gi'own, the annual average of rainy days is 

 thirty. 



Since the Mormons have settled in Utah, and planted considerable 

 trees, the waters of Salt Lake have risen seven feet. A correspond- 

 ent in Utah of the Agricultural Department, in June last, writes as 

 follows : 



"We must irrigate in most localities, but it has been demonstrated 

 that by planting trees and cultivating the soil the rainfall increases every 

 year, requiring constantly less irrigation. As we have not got the water 

 in all parts of the Territory, we resort to tree planting in the hope that it 

 will remedy the evil." 



