THE SUB-OCEANIC DEPRESSION, ETC. 423 
while at the same time there was no such enormous erosive 
power possessed by either of the then existing rivers, the 
Loire or the Gironde. 
With an added elevation of 9,000 or even of 7,000 feet not 
only the- higher and mountainous districts of France and 
Spain, and especially the Pyrenean region, but the whole of 
the area so raised would be brought under glacial conditions. 
The Pic de Nethou in Maladetta, Mont Perdu, and a few 
other summits in the Pyrenees about 10,000 feet in elevation, 
have glaciers at the present time, and there would be many 
more glaciers on the Pyrenean mountains were it not for the 
fact that their summits are not favourably grouped for the 
accumulation of great glacier-producing masses of snow. 
Under the conditions supposed, the whole range of the 
Pyrenees, including all its spurs and offshoots, would reach 
far above the snow-line. This mountain region is of con- 
siderable breadth, for the main sierra of the Pyrenees is 
buttressed, as it were, on each side by mountains for a 
distance of from fifteen to twenty miles from the axis of the 
range, giving a breadth, therefore, of from thirty to forty 
miles of mountains extending in length from the Bay of 
Biscay to the Mediterranean Sea. 
Although the summits of these mountains are not well 
adapted for the accumulation of snow and the formation of 
glaciers, this is not the case with those parts of the region 
now well below the snow-line, since there are innumerable 
valleys of great capacity amidst surrounding lofty hills and 
mountains, which if above the snow-line would retain snow 
and so accumulate sufficient material to produce very many 
and very large glaciers. Winds from the west and south- 
west, that is from the ocean, would prevail as now and bring 
with them enormous amounts of vapour and air charged with 
evaporated water from the warm surface waters of the 
equatorial seas and the scarcely less warm waters of the 
deflected equatorial current flowing north-eastward as now 
from the American continent, but, in consequence of the 
elevation of the West Indian, or the Antillean region, having 
a less northerly course. This vapour and water-gas would 
be rapidly condensed by the great cold of the mountains and 
plateaux, and the mountains being of great elevation, the 
atmosphere would be compelled to give up a very large 
proportion of its water. There would, consequently, be 
over the whole of the European south-west region an 
unusually great precipitation, and thus the material for the 
