THE SURFACE OF THE GLOBE. 33 



It is the theory of a fourth, that the tides of seven or eight hundred 

 fathoms have, on the contrary, carried off from time to time the bot- 

 toms of the sea, and cast them as mountains and hills in the vallies, or 

 on the primitive plains of the continent *. 



A fifth has thought that meteoric stones have fallen successively 

 from heaven, which have been the component parts of the earth, and 

 which bear the imprint of their strange origin in the unknown beings 

 whose relics they containf. 



A sixth makes the earth hollow, and places in the centre a diamond, 

 which conveys itself by intervention of comets from one pole to an- 

 other, drawing with it the centre of gravity and the mass of waters, 

 and thus alternately drowning the two hemispheres j. 



We could quote twenty other systems, equally contradictory with 

 these. And do not let us be understood as criticising the authors of 

 them ; on the contrary, we know that these opinions have generally 

 been elicited from men of genius and understanding, who were not 

 ignorant of facts, to examine which many of them had travelled far 

 and long, and have added many and important truths to the science. 



Causes of these Contradictions. 



How then can such opposing facts occur in the results of those who 

 have started with the same first principles to resolve the same problem ? 



Must it not be that the terms of the problem have not all been tho- 

 roughly considered ; which has left it to this day undetermined, though 

 capable of many solutions, all equally plausible when this or that con- 

 dition is overlooked; all equally unworthy of adoption when a new 

 condition arises, or when attention is arrested by some well-known 

 but neglected fact. 



The Nature and Terms of the Problem. 



To quit the language of mathematics, we will say that nearly all the 

 authors of these systems, having only regarded certain difficulties 

 which opposed them more forcibly than others, have solved them in a 

 manner more or less plausible, and have thrown aside others as nume- 

 rous and important. One, for instance, has only contemplated the 

 difficulty of changing the level of the sea ; another, that of dissolving 

 all terrestrial substances in one and the same liquid ; a third, that of 

 accounting for the existence of animals in the frigid zone, which he 

 supposed could only live in the torrid zone. Exhausting on these 



* Doloinieu, ibid. 



f MM. de Marscball : Rechercbcs sur l'Origine ct lc Dcveloppemcnt da l'Oidie 

 actucl du Monde. Giessen, 1802. 



+ M. Bertrand ; Renouvellement Peiiodique des Contmcns Terrestresi Hambourp, 

 1799. 



