EVILS FOLLOWING DESTRUCTION OF FORESTS. 4S 



with that which nature has arranged by the work of time 

 the work of ages. There is often destroyed in a few days 

 by man, through ignorance or cupidity, the work of hun- 

 dreds of centuries ; then, full of surprise at the disorder 

 occasioned by himself, he accuses Providence, makes proces- 

 sions and neuvaines [nine days' devotions, an observance 

 practised in the Romish Church], in order to conciliate 

 God; but taking good care not to think of himself as the 

 principal cause of the evil from which he is suffering.' 

 Viollet-le-Duc. 



6. ' It is especially necessary in warm countries to preserve 

 the forests, because on the one hand they keep down the 

 temperature, and because on the other they induce rains, 

 without which there is no vegetation possible. The salva- 

 tion of the colony of Algiers can only at this price be 

 secured.' Make. 



7. ' By the single act of a pioneer settler clearing virgin 

 soil, he alters the network of isothermal, isothermal, and 

 isochimenal lines [lines of equal mean temperature, of 

 equal summer temperature, and of equal winter tempera- 

 ture] over a country. One may say, in general terms, 

 that the forests are similar to the sea in their influence, 

 reducing the natural difference of temperature in the 

 different seasons, while the destruction of forests increases 

 the difference between the extreme heat and the extreme 

 cold, imparts greater violence to atmospheric currents and 

 to torrential rains, and a protracted duration to droughts. 

 . . . Marsh fevers even, and other epidemic diseases, 

 have often made an irruption into a district when woods, 

 or simple screens of protecting trees, have fallen under the 

 axe. As for the water-flow, and the climatic conditions 

 on which it depends, one cannot doubt for a moment that 

 the clearing away of woods has had the effect of disturbing 

 its regularity. The rain, which the interlaced branches of 

 the trees allow to fall drop by drop, and which would swell 

 up the spongy mosses upon which it fell, or which would 

 trickle slowly across the dead leaves, and the long fibrous 

 masses of the roots, flows away at once with rapidity over 



