Ixvi PROCEEDINGS OF THE GEOLOGICAL SOCIETY. 



sera, and had been called upon to decipher the monuments of a gla- 

 cial period of high relative antiquity, — had the phsenomena of the drift 

 constituted the first or oldest chapter then extant of the earth's auto- 

 biography, instead of happening to be, as it now is, the last and 

 newest, we should have been in danger of indulging for ever in the 

 most visionary and extravagant hypotheses. Ignorant of glaciers and 

 icebergs, and perhaps of ice and snow, — ^unable to comprehend the 

 nature of that mysterious power which had pohshed the surface of 

 rocks over wide areas, or had engraved upon them long rectilinear 

 and parallel furrows, we should have gazed upon these markings, and 

 upon the confused and unstratified heaps of clay and loam, inter- 

 spersed with boulders, and usually devoid of fossils, in stupid amaze- 

 ment and with feelings of despair. The enormous bulk of some erra- 

 tics, which had travelled for hundreds of miles from their original 

 sites, would have confounded us, and might well have tempted a 

 geologist to dream of frightful catastrophes, and diluvial waves of 

 prodigious velocity, which swept over the planet in its infancy, before 

 it was fitted for the reception of the higher animals and plants, much 

 less to become the home of man. If any one then doubted that there 

 had been an sera of paroxysmal violence, or of primaeval chaos, and 

 wished to refer all geological appearances exclusively to the agency 

 of slow and ordinary causes, he would have been asked to explain the 

 position of fragments of granite, like those of Scandinavian origin, 

 on the plains of Pomerania, or of protogene from Mont Blanc lodged 

 on the summit of the Jura, and such an appeal in refutation of a 

 theory apparently so visionary must have been triumphant. 



But it is now time to conclude ; and in taking leave of you. Gentle- 

 men, I will venture to indulge the hope, that on some future occasion 

 I may resume this theoretical discussion, which ought to embrace 

 every department of geological inquiry, including that of palaeontology, 

 to which as yet I have been able to make but a few passing allusions. 



