V 
THE MOUNTAINS OF SWITZERLAND. 83 
London Clay and other soft Eocene deposits of the 
South of England.” * 
Unfortunately we seldom see a map, except on 
quite a small scale, of the whole Alps. We have 
separate maps of France, of Switzerland, of Italy, and 
of the Austrian dominions. But to get a good general 
idea of the whole Alps, we require not only Switzer- 
land, but parts of France, Italy, and Austria. If we 
have such a map before us we see that, with many 
minor irregularities, the Alps are formed on a de- 
finite plan. 
The principal axis follows a curved line en- 
circling the North of Italy; commencing with a direc- 
tion almost due north in the Maritime Alps, sweeping 
round gradually to the east. The direction appears 
to have been determined by the pre-existing Central 
Plateau of France and the Black Forest, which pro- 
bably formed a continuous barrier before the sub- 
sidence of the Rhine valley. They are in fact ancient 
pillars, far older than the Alps, and Switzerland has 
been thrown into waves or folds by compression 
against these great buttresses. 
“To account for the conformation of the Alps,” 
says Tyndall, “and of mountain regions generally, 
constitutes one of the most interesting problems of 
* Geikie’s Text-book of Geology. 
6 * 
