Nalural Ilhtory. 1 8 1 



Indeed, its unreasonableness and extravaj^ance are 

 so great, that it seems to have attracted but little 

 respectful attention among any class of philoso- 

 phers. 



This theorist was succeeded by another, of the 

 same name, but a much more sober and rational 

 inquirer. In 1799 M. L. Bertrand, of Geneva, 

 published a work'" which was intended to account 

 for the phenomena of the globe we inhabit. 

 This gentleman supposes, with Dr. Halley, that 

 there is a magnetic nucleus enclosed and suspended 

 in a hollow space, in the centre of the earth. 

 This has a rotatory motion of its own, and an in- 

 clination of its magnetic axis to the axis of rota- 

 tion, thus causing an oscillatory motion in the 

 magnetic poles. While things were in this situa- 

 tion, he supposes that a Comet of ordinary size and 

 character approached our earth, displaced the nu- 

 cleus from the centre, removed it toward one side, 

 and changed the centre of gravity of the earth. 

 These circumstances occasioned the derangement 

 of the seas, their removal to other parts of the 

 globe, the immersion of old, and the emersion of 

 new continents. This theorist is a disciple of 

 M. De Saussure," and the principal design of his 

 work seems to have been to show the possibility 

 of that sudden retreat of the ocean which his 

 master believed in and taught, and to account for 

 that event, and the subsequent elevation of the 

 land which before formed its bottom. 



The last person to be mentioned, as having ad- 

 ventured in this ample field of speculation and 



m Renowotllemens Pertodiqtics, &C. Par L. Bertrand, &c. 8vo. 1799. 



« M. De Saussure had promised to give a geological system, at the 

 end of his Travels over the Alps; but after many y.'ars, lie contented 

 himself with informing the public, that the result of his investigations in- 

 duced him to believe, that the whole of our contineiits had been formed 

 under the sea, had been arranged by its action, and were left dry by a 

 precipitate retreat of its waters. 



