208 ON THE REVOLUTIONS 



dv alluded to, as indicated by the observations of Pallas ; by 

 which it appears that the skeletons, and even carcases of great 

 animals and fish, natives of the torrid zone, are found embed- 

 ded in the soil along the banks of the great Russian rivers, and 

 buried in the earth, in the frozen regions along the shores of 

 the North Seas, where thaw never penetrates more than a yard 

 below the surface. 



The series of inquiries, the result of which I have laid be- 

 fore the Society in the course of this season, was first sug- 

 gested to me by the vertical rents, filled with congealed lava, 

 which are visible on the craggy face of Somma, the ancient 

 part of Mount Vesuvius. They exhibit a clear view of those 

 restraints under which the eruptive efforts of volcanoes are 

 held in quiet times, and which are occasionally surmounted ; 

 and this circumstance, transferred by analogy to the plutonic 

 regions, has afforded, by means of the forcible intrusion of li- 

 quid granite, a satisfactory account of the convoluted structure 

 of the strata of killas, when in a semifluid and flexible state ; 

 the convolutions thus formed, furnishing an easy explanation 

 of vertical stratification. 



The same restraint, occasionally overcome, has explained 

 the protrusion of vvhinstone among the secondary strata, some- 

 times in vast beds parallel to them, and sometimes in huge 

 amorphous masses. The restraint exerted by these inflexible 

 obstacles, being surmountable only by acts of violence, I have 

 concluded that the elevations, both volcanic and plutonic, 

 must have been accompanied by a succession of powerful 

 starts \ and great part of these operations taking place un- 

 der the sea, that enormous waves must have been thus pro- 

 duced. In this manner, a satisfactory account has been furnished 

 of earthquakes, and of their attendant waves, as well as of the 

 overwhelming inundations alluded to in this paper, the reality 



of 



