CHAP. IX.] 



ANCIENT GLACIAL EPOCHS. 



173 



during some part of the Tertiary period these mountains may 

 have been far higher than they are now, and this we know 

 might be sufficient for the production of glaciers descending to 

 the sea-level, even were the climate of the lowlands somewhat 

 warmer than at present.-"- 



The weight of the negative evidence. — But when we proceed to 

 examine the Tertiary deposits of other parts of Europe, and 

 especially of our own country, for evidence of this kind, not 

 only is such evidence completely wanting, but the facts are of 

 so definite a character as to satisfy most geologists that it can 

 never have existed ; and the same may be said of temperate 

 North America and of the Arctic regions generally. 



In his carefully written paper on ''The Climate Controversy" 

 Mr. Searles V. Wood, Jun., remarks on this point as follows: 

 ''Now the Eocene formation is complete in England, and is 

 exposed in continuous section along the north coast of the Isle 

 of Wight from its base to its junction with the Oligocene (or 

 Lower Miocene according to some), and along the northern 

 coast of Kent from its base to the Lower Bagshot Sand. It has 

 been intersected by railway and other cuttings in all directions 

 and at all horizons, and pierced by wells innumerable ; while 

 from its strata in England, France, and Belgium, the most 



^ Prof. J. W. Judd says : " In the case of the Alps I know of no glacial 

 phenomena which are not capable of being explained, like those of New 

 Zealand, by a great extension of the area of the tracts above the snow-line 

 which would collect more ample supplies for the glaciers protruded into 

 surrounding plains. And wdien we survey the grand panoramas of ridges, 

 pinnacles, and peaks produced for the most part by sub-aerial action, we 

 may well be prepared to admit that before the intervening ravines and 

 valleys were excavated, the glaciers shed from the elevated plateaux must 

 have been of vastly greater magnitude than at present." (Contributions 

 to the Study of Volcanoes, Geological Magazine, 1876, p. 536.) Professor 

 Judd applies these remarks to the last as well as to previous glacial periods 

 in the Alps ; but surely there has been no such extensive alteration and 

 lowering of the surface of the country since the erratic blocks were de- 

 posited on the Jura and the great moraines formed in North Italy, as this 

 theory would imply. We can hardly suppose wide areas to have been 

 lowered thousands of feet by denudation, and yet have left other adjacent 

 areas apparently untouched ; and it is even very doubtful whether such 

 an extension of the snow-fields would alone suffice for the effects which 

 were certainly produced. 



