302 M. Ami Boue* on the Palaiohydrography 



oceans with islands, and we also find that these become more 

 free the further 1 we go back to the primitive times of the 

 earth. 



These oceans seem, according to the forms of the actual 

 continents and to their geognosy, to have extended in an 

 equatorial direction, exactly the contrary of our present 

 oceans, which are in the meridian direction. 



The islands and continents of those remote times extended, 

 on the other hand, especially N.S., such as the partly-de- 

 stroyed islands of Western Europe, Scandinavia, Arctic Ame- 

 rica, Eastern and Southern Asia, Southern Africa, the East- 

 ern partly-destroyed America, the Western America, the 

 Eastern New Holland. 



If we go still further back in the primary period, we find 

 many continents or islands which extend parallel to the 

 equator, viz., around both the poles, between the tropics, 

 and probably, also, in the warmer parts of the temperate 

 zones, but the seas or the subsidences were then exactly in 

 a contrary direction. 



Under the great causes of changes of the earth's surface, 

 we must next mention the dynamic motions, and also reckon 

 the destruction produced by the eternal tendency of the water 

 to turn round the middle of the earth as much as possible 

 after the astronomical laws. 



When we are forced to admit the mentioned cruciform al- 

 ternation of the dynamic relations, it is only what we would 

 expect to find in a spheroidal body which has an igneous 

 fluidity in the interior, a rigid surface partly covered with 

 water, and turning round itself. Every one admits that the 

 centrifugal force in the course of time has given rise to a 

 flattening of the poles, as well as to an elevation against 

 the equator ; but this change in the spheroid must have pro- 

 duced rents and subsidences in both equatorial and meri- 

 dian-like directions. According to mathematical laws, the 

 equatorial subsidences were contemporaneous with the ele- 

 vations, but not with the meridian-like subsidences, because 

 these appeared later, and owing to new elevated parts of the 

 earth's surface, resulting from the subsidence of the rigid 

 parts upon the molten mass, and these parts appear to have 



