224 TIMBERS AND THEIR USES 



of Lake Valencia. After comparing its condition 

 with the descriptions of older writers, he became 

 convinced that the area of its waters had very 

 much diminished. Subsequently, he made a 

 most careful examination of the circumstances, 

 and came to the conclusion that the serious 

 shrinkage was due to the extensive clearings of 

 the surrounding forests which had been made 

 during the previous half-century. In discussing 

 the matter in his Travels, he makes this pregnant 

 observation : ' In felling the trees which cover 

 the tops and sides of mountains, men in every 

 climate prepare two calamities for future genera- 

 tions — a want of wood and a scarcity of water.' 

 Some twenty-five years afterwards, M. Boussin- 

 gault visited the valley. The inhabitants informed 

 him that not only had the" shrinkage ceased, 

 but that the lake had risen perceptibly. But 

 in the meantime great political changes had 

 occurred ; wars had ravaged the country and 

 greatly reduced the inhabitants, the tillage of 

 the soil had been almost abandoned, and the 

 tropical forest which so quickly reproduces itself 

 on abandoned clearings had regained possession 

 of the soil. 



" In the Island of Ascension, it is said, there 

 was a fine spring, which was situated at the 

 foot of a mountain originally covered with trees. 

 The flow from this spring gradually shrank and 



