President of the Geological Society for 1850. 39 



Bunbury, has argued, rather the absence of frost than, as 

 many botanists once thought, an intense tropical heat. M. 

 Adolphe Brongniart, in his admirable Essay on the genera 

 of Fossil Plants, published in the year 1849,* has questioned, 

 and apparently with reason, the proofs hitherto adduced in 

 favour of the existence of any true palms in the coal- 

 measures, and Mr Bunbury considers their absence as af- 

 fording an additional argument to that derived from the 

 universal preponderance of ferns in favour of a mild tem- 

 perature in the atmosphere, — a warm, moist and uniform 

 climate, not a tropical one. The flora, he says, of the 

 London clay was of a much more tropical character. In 

 this manner we may now reason philosophically on the 

 remote carboniferous era according to strict rules of induc- 

 tion ; but had we lived in that era, and had been called upon 

 to decipher the monuments of a glacial period of high re- 

 lative antiquity, — had the phenomena of the drift consti- 

 tuted the first or oldest chapter then extant of the earth's 

 autobiography, 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 polished the surface of rocks over wide 

 areas, or had engraved upon them long rectilinear and 

 parallel furrows, we should have gazed upon these mark- 

 ings, and upon the confused and unstratified heaps of clay 

 and loam, interspersed with boulders, and usually devoid of 

 fossils, in stupid amazement and with feelings of despair. 

 The enormous bulk of some erratics, which had travelled for 

 hundreds of miles from their original sites, would have con- 

 founded us, and might well have tempted a geologist to 

 dream of frightful catastrophes, and diluvial waves of pro- 

 digious 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 era of paroxysmal 

 violence, or of primeval chaos, and wished to refer all geo- 



* Tableau des genres, etc. Dictionnaire Universelle d'Histoire Nat., Art. 

 V6g^taux Fossiles. 



