44 Correspondence— -Mr. Clement Reid. 



recently made in this country that the conclusion has been arrived 

 at, but my impression after reading a number of foreign papers is 

 that for this particular period we are a good deal in advance of most 

 other nations. The wonderful variety of the beds in Britain, their 

 fossiliferous character, and the splendid series of cliff sections and 

 caves in our islands has given us unequalled opportunities for the 

 study ; opportunities well used by such careful observers as Lj^ell, 

 Prestwich, Eamsay, Geikie, and Boyd Dawkins. In most parts of the 

 Continent the Pleistocene deposits appear to be represented hj one 

 tolerably uniform mass, like the Loess of the Ehine or the Tundras 

 of Siberia ; but in England we have beds showing great alternations 

 of climate, but gradual changes allowing time for the migration of 

 species. 



Frozen carcases of Mammoth and Ehinoceros were spoken of as 

 of occasional occurrence, for the gi'eater number that are found are 

 merely skeletons, or portions of skeletons, from which the flesh has 

 long decayed. The extermination of the Mammoth in Britain and 

 Germany may be referable to human agency, while in Siberia it was 

 gradually killed by the increase of cold and want of food — there is 

 as yet no evidence that the extinction in the different districts was 

 simultaneous. A change of temperature of 1° in a century would be 

 extremely rapid from a geological point of view ; but Mr. Howorth 

 would bring into play a change of probably 20° in a few months. 

 At present only two modes are known by which a marked alteration 

 of the climate can be brought about, extensive modification in 

 physical geography and astronomical changes ; but both these would 

 be of slow operation, and unless a strong case can be made out, we 

 can scarcely accept a sudden fall of temperature referable to no 

 known cause. 



Perhaps Mr. Howorth, as an antiquary, is inclined to pay more 

 attention to authority than a field geologist is likely to do ; but the 

 training on the Geological Survey is such as to lead one to believe 

 nothing we are told and only half what we see. Of course, if 

 we accept such authorities as Cuvier, Buckland, and d'Archiac as 

 examples of modern opinion, diluvial theories are still in full vigour. 

 But the systematic study of Pleistocene Geology onlj' commenced 

 about forty years ago, and even now the beds are often treated as 

 abnormal deposits, to which ordinaiy rules do not apply. 



Mr. Howorth scarcely does justice to the views of the followers of 

 Hutton and Lyell, for the uniformitarian theory does not necessarily 

 preclude much more rapid changes than are now taking place. 

 After several years study of Pleistocene Beds, I think that, as a 

 rule, things did then progress faster, and that we are now in a period 

 of exceptionally slow changes. I take uniformitarianism to mean 

 that no cataclysmic explanations must be adopted until it is clearly 

 proved that the phenomena are inexplicable by reference to forces 

 now in operation, and it is only from this point of view that I have 

 ventured to criticize Mr. Ho worth's papers. 



"WlTHERNSBA, HuLL, ClEMENT EeID. 



Dec. dth, 1881. 



