122 



SUPPOSED CONTEMPORANEOUS UPHEAVAL 



[Or. VII. 



Beaumont 



com 



earth there have been long periods of 



during which the deposition of sedimentary matter has gone 



on in regular continuity ; and there have also been short 



rsmai 



was broken. 



7 



c 2dly. At each of these periods of violence or " revolu- 

 tion/' in the state of the earth's surface, a great number of 

 mountain-chains have been formed suddenly. 



' 3dly. The chains thrown up by a particular revolution 

 have one uniform direction, being parallel to each other 

 within a few degrees of the compass, even when situated in 

 remote regions; whilst the chains thrown up at different 

 periods have, for the most part, different directions. 



< 4thly. Each " revolution," or " great convulsion," has 

 fallen in with the date of another geological phenomenon ; 

 namely, " the passage from one independent sedimentary 

 formation to another," characterised by a considerable dif- 

 ference in " organic types. 



?? 



c 5thly. There has been a recurrence of these paroxysmal 



movements from the remotest geological periods ; and they 

 may still be reproduced, and the repose in which we live may 

 hereafter be broken by the sudden upthrow of another system 

 of parallel chains of mountains. 



' 6thly. The origin of these chains depends not on partial 

 volcanic action, or a reiteration of ordinary earthquakes, but 

 on the secular refrigeration of the entire planet. For the 

 whole globe, with the exception of a thin envelope, much 

 thinner in proportion than the shell to an egg y is a fused 

 mass, kept fluid by heat, but constantly cooling and con- 

 tracting its dimensions. The external crust does not gradu- 

 ally collapse and accommodate itself century after century to 

 the shrunken nucleus, subsiding as often as there is a sligW 

 failure of support, but it is sustained throughout whole 

 geological periods, so as to become partially separated from 

 the nucleus, until at last it gives way suddenly, cracking and 



May, 1847. The latest edition of M. 

 de Beaumont's theory will be found in 

 the 12 th vol. of thePictionnaireUniversel 



d'Hist, Nat. 1852, art. 

 Montagnes ; ' also the 

 separately. 



< Systemes de 

 same printed 



