394 STRUCTURE, AND MODE OP ACTION OF VOLCANOS. 



forth through the many openings of the deeply fissured crust of the 

 globe may have favored, perhaps for centuries, the growth of palms 

 and tree-ferns and the existence of animals requiring a high tempe- 

 rature, over entire countries where now a very different climate 

 prevails. According to this view of things (a view already indi- 

 cated by me, in a work entitled " Geological Essay on the Super- 

 position of Kocks in both Hemispheres"), the temperature of 

 volcanos would be that of the interior of the earth ; and the same 

 cause which, operating through volcanic eruptions, now produces 

 devastating effects, might in primeval ages have clothed the deeply 

 fissured rocks of the newly oxidized earth in every zone with the 

 most luxuriant vegetation. 



If, with a view to explain the distribution of tropical forms whose 

 remains are now discovered buried in northern regions, it should be 

 assumed that the long-haired species of Elephant now found en- 

 closed in ice was originally indigenous in cold climates, and that 

 forms resembling the same leading type may, as in the case of lions 

 and lynxes, have been able to live in wholly different climates, still 

 this manner of solving the difficulty presented by fossil remains 

 cannot be extended so as to apply to vegetable productions. From 

 reasons with which the study of vegetable physiology makes us 

 acquainted, Palms, Musaceae, and arborescent Monocotyledones, are 

 incapable of supporting the deprivation of their appendicular organs 

 which would be caused by the present temperature of our northern 

 regions ; and in the geological problem which we have to examine, 

 it appears to me difficult to separate vegetable and animal remains 

 from each other. The same mode of explanation ought to compre- 

 hend both. 



I have permitted myself at the conclusion of the present dis- 

 cussion to connect with facts collected in different and widely sepa- 

 rated countries some uncertain and hypothetical conjectures. The 

 philosophical study of Nature rises beyond the requirements of a 

 simple description of Nature : it does not consist in a sterile accu- 

 mulation of isolated facts. It may sometimes be permitted to the 

 active and curious mind of man to stretch forward from the present 

 to the still obscure future ; to divine that which cannot yet be 

 clearly known; and thus to take pleasure in the ancient myths of 

 geology reproduced in our own days in new and varied forms. 



