540 Natural Jlisfory, [Chap. III. 



been compelled to seek for other means of immerg^ 

 ing the present continents in the ocean*. 



Finally, the researches of modern geologists 

 have given abundant confirmation to the sacred 

 history, not only with respect to the general de- 

 luge, but also with regard to the age of the earth f. 



* M. Bailly of France at fkst embraced the theory of the 

 earth proposed by Buftbn ; but finding the evidence arising from 

 the investigations of natural history, and from universal tradition, 

 so strongly to attest the reality of the ger)eral deluge, he abandon- 

 ed tliat delnsive theoiy, and took refuge ,in another system, in 

 which he recognises the deluge, and only contends for placing it 

 as far back as three thousand five hundred years before Christ. 



f Sir William Hamilton and Mr. Ferber particularly applied 

 themselves to the study of volcanoes, without giving general 

 systems. They affirmed that the indications furnished by sub- 

 terraneous and volcanic phenomena, and particularly by the beds 

 of lava, announce the antiquity of tlie earth to be far greater than 

 the sacred histor}' represents it. But the}' did not advert to the 

 fact, that all lavas are not composed of the same substance. AH 

 have not undergone the same degree of vitrification, and of course 

 are more or less susceptible of decomposition. And even when 

 their composition is the ?.ame, much depends on tlie state m 

 \\ Inch they are emitted. When pom*ed from the crater in the 

 fermentation of boiliiu^" li(iuefaction, a .scoria (or dross) rises, like 

 broken waves, on the surface, and is easily pulverised by the air 

 and wcatlier. When the heat is less violent, or when the torrent 

 ii cooled in its course, an even and almost impenetrable surface 

 defies th.e influence of the atmosphere. These philosophers do 

 not recollect \.\vd\. I Icvcidaneum, the date of the destruction of which 

 is w ell known, is covered by nearly scrcnii/. feet of lava, interspersed 

 with ficzcn distinct seams of friable earth j and the whole covered 

 with good soil ; yet all tliis has been the midoubted production of 

 I'.-^sS tiian ci^luccii huxJrcd ycui;>. — Howard's Thoughts on the. 

 (Jhjhe. 



In hke manner, count Ijorch, in his Letters on Sicilj/ and Malta, 

 professes to believe that ul^tna is at least eight thousand years old, 

 w hich lie infers from the beds of vegetable earth which he disco 

 vered betv/ecn different beds of lava. Yet M. Dolomieu, who 



