GEOLOGY. 



OHANaES OP CLIMATE IN POST-GLACIAL TIMES. 

 By JAMES GEIKIE, LL.D., F.R.S. 



ALTHOUGH much has been written about the character of 

 our cHmate in post-glacial times, yet the subject is far 

 from being exhausted. No little complication has arisen from the 

 fact that many deposits which have been described as post- 

 glacial, really appertain to the preceding glacial period, and are 

 to be classed as of inter-glacial age. Such, for example, are the 

 palaeolithic and ossiferous accumulations in many English caves, 

 as also those ancient " river-drifts " of southern England and the 

 Continent which have yielded similar remains. In the present 

 paper, I define as post-glacial only those deposits which can be 

 proved to have been laid down at a period subsequent to the 

 disappearance of the last great ice-sheet of northern and north- 

 western Europe. 



In common with other geologists, I have maintained that we 

 have no evidence in these deposits for any great oscillations of 

 climate — no mutations at all comparable in magnitude to those 

 which took place during the preceding glacial or pleistocene 

 period. My belief has been, that with minor fluctuations, such 

 as might be caused by changes in the distribution of land 

 and sea, the climate of our islands has passed gradually from an 

 arctic to a temperate condition, and is now milder than it has 

 ever been since the close of glacial times. I have come to think, 

 however, that this is too broad a statement, and now incline to 

 the opinion that the climate of the post-glacial period, although 

 most probably never so warm as that of the last inter-glacial epoch, 

 was yet for some time marked by a more genial temperature than 

 we now enjoy, and that this milder epoch was followed by what 

 appears to have been a relapse to colder conditions than the 

 present. 



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