16 Cuvier''s Biographical Memoir of M, de Lamarck, 



responding theory of the formation of the globe and its changes, 

 founded on the supposition that all composite minerals are the 

 remains of living beings. The seas, unceasingly agitated by the 

 tides, which the action of the moon produces, are continually 

 hollowing out their bed ; and in proportion as the latter deepens 

 in the crust of the earth, it necessarily follows that their level 

 lowers, and their surface diminishes ; and thus the dry land> 

 formed, as has been already said, by the debris of living crea- 

 tures, is more and more disclosed. As the lands emerge from 

 the sea, the water from the clouds forms currents upon their sur- 

 face, by which they are rent and excavated, and divided into 

 valleys and mountains. With the exception of volcanoes, our 

 steepest and most elevated ridges have formerly belonged to 

 plains, even their substance once made a part of the bodies of 

 animals and plants ; and it is in consequence of being so long 

 purified from foreign principles that they are reduced to a sili- 

 ceous nature. But running waters furrow them in all directions, 

 and carry their materials into the bed of the sea^ and the latter, 

 from continual efforts to deepen its bottom, necessarily throws 

 them out on some side or other. Hence there results a general 

 movement, and a constant transposition of the ocean, which has 

 perhaps already made several circuits of the globe. This shift- 

 ing cannot occur without displacing the centre of gravity in the 

 globe ; a circumstance which, according to Lamarck, would have 

 the effect of displacing the axis itself, and changing the tempe- 

 ratures of the different climates. If none of these things have 

 fallen under our observation, it is on account of the excessive 

 slowness with which these operations are carried on. Time is 

 always necessary to account for them ; unlimited time, which 

 plays such an important part in the religion of the magi, is no less 

 necessary to Lamarck's physics, and it was to it that he had re- 

 course to silence his own doubts, and to answer all the objections 

 of his readers. 



The case was no longer the same, when he ventured to make 

 an application of his systems to phenomena capable of being ap- 

 preciated by near intervals. He had soon an opportunity of 



of seas, and its successive shifting to different points of the globe ; finally, on 

 the changes which living bodies produce on the nature and condition of the 

 surface. 1 voL 8vo. 1802, 



