EFFECTS OF FORESTS ON RIVEKS IN AMERICA. 167 



thirty years ago ; and there is less rain in the summer. Many of 

 the old trout streams of twenty years ago are now completely dry, 

 aad several parts of the State suffer more than formerly from 

 droughts. Snow covers and protects the ground with less 

 regularity." 



There is thus brought before us also another of the effects of forests, 

 or rather of the destruction of forests, but the discussion of this 

 cannot be prosecuted here without distracting attention from what 

 more immediately concerns us. 



Mr Marsh in his treatise on " The Earth as Modified by Human 

 Action," in writing of the Influences of the Forest on the flow of 

 springs, says :^-" It is an almost universal and, I believe, well-founded 

 opinion, that the protection afforded by the forest against the escape 

 of moisture from its soil by superficial flow and evaporation insures 

 the permanence and regularity of natural springs, not only within 

 the limits of the woods, but at some distance beyond its borders, and 

 thus contributes to the supply of an element essential to both 

 vegetable and animal life. As the forests are destroyed, the springs 

 which flowed from the woods, and, consequently, the greater water- 

 courses fed by them, diminish both in number and volume. This 

 fact is so familiar in the American States and the British Provinces, 

 that there are few old residents of the interior of those districts who 

 are not able to testify to its truth as a matter of personal observation. 

 My own recollection suggests to me many instances of this sort, and 

 I remember one case where a small mountain spring, which dis- 

 appeared soon after the clearing of the ground where it rose, was 

 recovered about twenty years ago, by simply allowing the bushes and 

 young trees to giow up on a rocky knoll, not more than half an acre 

 in extent, immediately above the spring. The ground was hardly 

 shaded before the water reappeai-ed, and it has ever since continued 

 to flow without interruption. The hills in the i^tlantic States 

 formerly abounded in springs and brooks, but in many parts of these 

 States which were cleared a generation or two ago, the hill-pastures 

 now suffer severely from drought, and in dry seasons furnish to 

 cattle neither grass nor water." 



And in regard to the effect of the destruction of forests on the 

 diminution of springs, he subsequently says there is no want of 

 positive evidence on the subject. 



Marchand cites the following instances : — 



" Before the felling of the woods, within the last few years, 

 in the valley of the Soulce, the Combe-^s-Mounin and the Little 



