THE EARTH. 43 



luxuries of man than his necessities, yet even to the last, she 

 continues her kind indulgence, and when life is over, she piously 

 covers his remains in her bosom. 



This external and fruitful layer which covers the earth, is, as 

 was said, in a state of continual change. Vegetables, which 

 are naturally fixed and rooted to the same place, receive their 

 adventitious noxuishment from the surrounding earth and water ; 

 animals, which change from place to place, are supported by 

 these, or by each other. Both, however, having for a time enjoyed 

 a life adapted to their nature, give back to the earth those spoils, 

 which they bad borrowed for a very short space, yet still to be 

 quickened again into fresh existence. But the deposits they 

 make are of very dissimilar kinds, and the earth is very differently 

 enriched by their continuance : those countries that have for 

 a long time supported men and other animals, having been ob- 

 served to become every day more barren ; while, on the contraiy, 

 those desolate places, in which vegetables only are abundantly 

 produced, are known to be possessed of amazing fertility. " In 

 regions which are uninhabited," ^ says Sir Buffon, " where the 

 forests are not cut down, and where animals do not feed upon 

 the plants, the bed of vegetable earth is constantly increasing. 

 In all woods, and even in those which are often cut, there is a 

 layer of earth of six or eight inches thick, which has been 

 formed by the leaves, branches, and bark, which fall and rot 

 upon the ground. I have frequently observed on a Roman way, 

 which crosses Burgundy, for a long extent, that there is a bed 

 of black earth, of more than a foot thick, gathered over the 

 stony pavement, on which several trees, of a very considerable 

 size, are supported. This I have found to be nothing else than 

 an earth formed by decayed leaves and branches, which have 

 been converted by time into a black soil. Now as vegetables 

 draw much more of their nourishment from the air and water 

 than they do from the earth, it must follow that in rotting upon 

 the ground, they must give more to the soil than they have 

 taken from it. Hence, therefore, in woods kept a long time 

 without cutting, the soil below increases to a considerable 

 depth; and such we actually find the soil in those American 

 H'ilds, where the forests have been undisturbed for ages. But 



3 Buffon, vol. i. p. 35a 



