28 A HISTORY OF 



composed -, these all lying horizontally one over the other, like the 

 leaves of a book, and each of them composed of materials that increase 

 in weight in proportion as they lie deeper. This is, in general, the 

 disposition of the different materials, where the earth seems to have 

 remained unmolested ; but this order is frequently inverted ; and we 

 cannot tell whether from its original formation, or from accidental 

 causes. Of different substances, thus disposed, tlfe far greatest part 

 of our globe consists, from its surface downwards to the greatest 

 depths we ever dig or mine * 



The first layer that is most commonly found at the surface, is that 

 light coat of blackish mould, which is called by some garden earth. 

 With this the earth is every where invested, unless it be washed off by 

 rains, or removed by some other external violence. This seems to 

 have been formed from animal and vegetable bodies decaying, and 

 thus turning into its substance. It also serves again as a storehouse, 

 from whence animal and vegetable nature are renewed, and thus are 

 all vital blessings continued with unceasing circulation. This earth, 

 however, is not to be supposed entirely pure, but is mixed with much 

 stony and gravelly matter from the layers lying immediately beneath 

 it. It generally happens, that the soil is fertile in proportion to the 

 quantity that this putrified mould bears to the gravelly mixture ; and 

 as the former predominates, so far is the vegetation upon it more lux- 

 uriant. It is this external covering that supplies man with all the true 

 riches he enjoys. He may bring up gold and jewels from greater 

 depths ; but they are merely the toys of a capricious being, things up- 

 on whrch he has placed an imaginary value, and for which fools alone 

 part with the more substantial blessings of life. " It is this earth," 

 says Pliny ,t " that, like a kind mother, receives us at our birth, and 

 sustains us when born. It is this alone, of all the elements around us, 

 that is never found an enemy to man. The body of waters deluge 

 him with rains, oppress him with hail, and drown him with inunda- 

 tions. The air rushes in storms, prepares the tempest, or lights up 

 the volcano ; but the earth, gentle and indulgent, ever subservient to 

 the wants of man, spreads his walks with flowers, and his table with 

 plenty ; returns with interest every good committed to her care ; and 

 though she produces the poison, she still supplies the antidote ; though 

 constantly teazed more to furnish the luxuries of man "than his neces 

 sities, 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 nourish- 

 ment 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 had 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 

 \n very differently enriched by their continuance : those countries that 



* Woodward, p. 9. f Plinii Naturalis Historia. lio. li. rp. 6*. 



