12 NATURAL HISTORY. 



we not find the materials which compose the earth hud- 

 dled together without order ? Why are not rocks, mar-- 

 bles, clays, marlcs, &c. scattered promiscuously, or 

 joined by irregular or vertical strata ? Why are not 

 heavy bodies found in a lower situation than light ones ? 

 It is easy to perceive, that this uniformity of nature, 

 this species of organization, this union of different ma- 

 terials by parallel strata, without regard to their weights 

 could only proceed from a cause equally powerful and 

 uniform as the motions of the .sea, produced by regu- 

 lar winds, or by the flux and reflux, &c 



As these causes act with superior force under the 

 equator than in other climates, the chains of mountains 

 are most extensive in its neighbourhood. Thus the 

 mountains of Africa and Peru are both the highest and 

 most extensive in the world. The mountains of Europe 

 and Asia, which extend from Spain to China, are not 

 so high as those of Africa and South America. Be- 

 sides, in the northern seas, the islands are but few, 

 when compared with those in the Torrid Zone. As 

 islands, therefore, are nothing but the summits of moun- 

 tains, it is clear there are more inequalities on the sur- 

 face of the earth near the equutor than in northerly 

 climates. 



Those vast chains of mountains which run from west 

 to east in the old continent, and from north to south 

 in the new, must have been formed by the general mo- 

 tion of the tides. But the origin of smaller mountains 

 and hills may be ascribed to particular motions occasion- 

 ed by winds, currents, and other irregular agitations 

 of the sea, or to a combination of all those motions 

 which are capable of infinite variations. 



But how has it happened that this earth, which, . 

 from time immemorial, hus been an kmncnse continent.. 



