LABBCHE AND MICHEL CHEVALIER. 69 



" I have by no means the intention to infer from what has been said 

 that the disintegration of soil is not generally greater under the tropics 

 than in temperate climates ; it has been my desire simply to establish that 

 in both cases the soil receives, from the vegetables which cover it, a pro- 

 tection proportionate to the destructive influence to which it is exposed. 

 Let us suppose that there should occur in England one of those rainy 

 seasons so common under the tropics. No doubt -.great extents of land 

 would be washed away, and the barrows, of which we have already spoken, 

 would quickly disappear. If, on the contrary, there fell there only the 

 same quantity of rain which we have every year in the climate of England, 

 we would find scarcely any traces of vegetation in the low-grounds, for the 

 water produced by it would be insufficient to sustain tropical plants, and 

 while it tended to disintegrate the soil, it would be so speedily evaporated that 

 its destructive action would be scarcely perceptible. The quantity of rain and 

 the vegetation are proportionate to one another; nevertheless, the disintegra- 

 tion of the soil increases with the quantity of rain, and the force of many 

 meteoric agents, in such a way that, other things being equal, the greater 

 the rainfall the greater is the destruction of the soil ; and consequently, 

 the warmer the climate, the more considerable is the disintegration of 

 the mountains. 



" In tropical regions, parasitical and creeping plants are seen in all 

 directions, growing wherever it is at all possible to do so, and with such 

 luxuriance as to render the forest almost impassable. The forms and the 

 leaves of trees, and of such plants, are admirably adapted to resist great 

 rains, and to protect the innumerable creatures which, in the rainy season, 

 come to seek a shelter under their foliage. The noise which the tropical 

 rains make in falling on these forests strikes strangers with astonishment ; 

 it is heard at distances which would be almost incredible to the inhabi- 

 tants of temperate regions ; and the rain, thus deadened and broken in its 

 fall, is speedily absorbed by the soil ; whereas, where it flows into hollows, 

 it produces torrents, which every one must confess are rather impetuous, 

 and cause great ravages." 



M. Michel Chevalier, in his work entitled Des Interets Mathiels de la 

 France, writes thus : — ■" Besides the works executed in the river-bed, there 

 are other measures which, according to men of experience, would exercise a 

 salutary influence on the navigability of natural water-courses, and which 

 concern even canals, as to feed these recourse must be had to rivers and to 

 the smallest streams. I wish to speak specially of the replanting of moun- 

 tains which have been so improvidently despoiled of their woods, and 

 abandoned in their nakedness by a culpable indolence, or even by a fatal one, 

 descending to niggardly interests, which the law does not recognize, but on 

 the contrary resents, have hindered the forests from reproduction by the effort 

 of nature alone. The rains and the snows, when they fall on the bald heights, 

 flow away or evaporate with the greatest rapidity ; in place of maintaining 

 brooks and rivers, on the rich levels, by which boatmen may profit, and on 

 which the proprietors of river-banks may felicitate themselves, they produce 

 there sudden floods, inundations which suspend navigation, devastate pro- 

 perties, covering them with gravel, and sometimes eating into them and 

 carrying them away ; then, after these floods, there follow soon low waters 

 which only stop at distant points and for a short time after some storm. 



Through reckless deforesting our temperate countries are thus being assimi- 



