40 THEORY OF THE EARTH. 



formed seas, which afterwards deposited the lime- 

 stone formations. 



By Demaillet the whole glohe was conceived 

 to have been covered with water for many thou- 

 sands of years. He supposed this water had gra- 

 dually retired ; that all the land animals were ori- 

 ginally inhabitants of the sea ; that man himself 

 commenced his career as a fish ; and he asserts, 

 that it is not uncommon, even now, to meet with 

 fishes in the ocean, which are still only half con- 

 verted into men, but whose descendants will in 

 time become perfect human beings *. 



The system of Buffon is merely an extension 

 of -that of Leibnitz, with the addition only of a 

 comet, which, by a violent blow, struck off from 

 the sun the liquefied mass of the earth, together 

 with those of all the other planets at the same 

 instant. From this supposition, he was enabled 

 to assume positive dates, as, from the present tem- 

 perature of the earth, it could be calculated how 

 long it had taken to cool down so far ; and, as all 

 the other planets had come from the sun at the 

 same time, it could also be calculated how many 

 ages are still required for cooling the greater 

 ones, and to what degree the smaller are already 

 irozenf. 



* Telliamed. Amsterd. 1748. 



t Theorie de la Terre, 1749; and Epoques de la Nature, 

 1775. 



