James Geikie — On Changes of Climate. 259 



present coast-line not mucli below where it stands now. But to 

 adduce proof of this would lead me into too much detail, and I shall 

 therefore take the liberty of assuming that before the process of 

 subsidence commenced in Italy, the shores of that country and of 

 Britain occupied very much the same position as at present. It 

 is evident, on the hypothesis referred to above, that long before the 

 interglacial submergence in Italy (so-called pliocene beds) could 

 reach its climax, Britain would become continental. An elevation 

 of only 120 feet or thereby would be sufficient to effect a junction ; 

 and even if the upheaval in Britain reached but half the extent that 

 the subsidence ultimately attained in Italy, the sea must have well- 

 nigh vanished from the bed of the German Ocean and the English 

 Channel at a time when the waves were washing the base of the 

 Italian Alps. Such a continental condition would probably endure 

 for a lengthy period, to be measured by the time required for the 

 subsidence of Piedmont, the accumulation of the so-called " Pliocene 

 sands," and the partial re-elevation of the land. For if, during the 

 subsidence of Piedmont, Britain became continental before that 

 downward movement was completed, our country would continue 

 in the same condition for some time even after the re-elevation of 

 Italy had begun. But as Italy mounted higher and higher, the sea 

 would gradually steal in between Britain and the Continent until 

 complete insulation was brought about. Thereafter, the subsidence 

 in Britain continued until the Welsh mountains were laved at a 

 height above the present coast-line of not less than 1400 or even 2000 

 feet. With such excessive depression in the north of Europe — a 

 depression that brought the sea over a large part of Scandinavia, 

 Eussia, Germany, Denmark and Holland — it may be inferred that 

 the elevation in the south of Europe raised far above the sea-level 

 grounds which now lie drowned in the Mediterranean.^ 



In the early stages of this period of elevations and depressions the 

 climate would appear to have been mild and genial all over Europe ; 

 indeed, it is very doubtful whether any glaciers existed in Britain at 

 this time. For the climate of the last interglacial period may fairly 

 be inferred to have been as genial as the succeeding glacial period 

 was cold. It was under such conditions that the Elephant, the 

 Ehinoceros and other extinct mammalia inhabited Switzerland. 

 Then, too, Man and the great pachyderms (Ehinoceros, Hippo- 

 potamus, etc.) may have crossed into Britain — but not for the first 

 time. Some portion of the English river-gravels and cave-deposits 

 I would therefore refer to this period. Of course I am aware that 

 no traces of this old land-surface have yet been detected underneath 

 the kames of Scotland. But as the very presence of these deposits 

 presupposes great denudation, the absence of any traces of a land- 

 surface is hardly to be wondered at. In this connexion, however, I 

 would refer to the peat (with palEeolithic implements and bones of the 



1 If the upheaval id the south of Europe at all equalled the depression in the 

 north, it can hardly he doubted that there would be land communication between 

 Africa and Europe— the soundings between Sicily and Cape Bon indicating the 

 presence of a submarine ridge within less than ipo fathoms from the surface. 



