Notice of the Wendells of Geology. 15 



" But ought we to rest content in the assumption that all these 

 wonderful manifestations of Creative Intelligence were solely de- 

 signed to contribute to our physical necessities and gratifications ? 

 Say, rather, that this display of beauty, power, and goodness, was 

 designed to fill the soul with high and holy thoughts — to call 

 forth the exercise of our reasoning powers — to excite in us those 

 ardent and lofty aspirations after truth and knowledge, which ele- 

 vate the mind above the sordid and petty concerns of life, and 

 give us a foretaste of that high destiny, which we are instructed 

 to hope may be our portion hereafter ! 



'• Geological theory of Leibnitz. — If we extend our views be- 

 yond the limits of strict induction, and venture to speculate on 

 the condition of our globe in the dawn of its existence, and in 

 those remote periods of which the physical characters are in- 

 scribed on the rocks and mountains, it appears to me that the 

 theory of Leibnitz, which embraces the original nebular condi- 

 tion of the solar system, and assumes a former incandescent state 

 of this planet, and its gradual refrigeration, is the only h3^pothe- 

 sis in harmony with the present state of astronomical and geolo- 

 gical knowledge. The prevalence of a higher temperature in 

 northern latitudes during the deposition of the secondary forma- 

 tions, was indicated by the fossil remains of animals and plants 

 of a tropical character. If we admit of a progressive cooling of 

 the earth, we necessarily infer that in the most ancient epochs, 

 the infinence of the internal heat upon the earth's surface was 

 very considerable, and that it gradually decreased, till it arrived 

 at the present condition of things, in which the surface tempera- 

 ture is scarcely, if at all, affected by radiation from within. As- 

 suming then as an established theory, what at present, perhaps, 

 must only be regarded as a highly philosophical and probable 

 speculation, we can readily understand that during the secondary 

 geological eras, the temperature of the surface may have been 

 so augmented by a supply of heat from an internal source, as 

 to have maintained a climate possessing the conditions required 

 for the existence of corals in the seas, and of forests of palms 

 and tree ferns, and swarms of reptiles, on the islands and conti- 

 nents of northern latitudes.* The climate of particular latitudes 



* See an excellent summary of the present state of geological theory in Phillips's 

 Treatise on Geology. 



