in Europe and North America. 331 
of many persons the idea that the elevation has been produced 
by some force acting from below, along a line in the case of a 
chain, and on a point of greater or less extent when the moun- 
tains lie in a cluster, as a whole, more or less dome-shaped. 
Such forces would stretch the strata; and, when they could no 
longer stand the tension, cracks would ensue, and many lines of 
valley are assumed to lie in such fractures. But in Wales, the 
Highlands of Scotland, and more notably in the Alps, the strata 
now visible have been compressed and crumpled, not stretched, 
and they occupy a smaller horizontal space than they did pre- 
. 
vious to the formation of the chain 
Contortions that since disturbance have been exposed by denuda- 
lon; otherwise the rocks would not be cleaved. I therefore do 
Switzerland, there are any lakes now occupying yawning frac- 
ures, consequent in Switzerland on Post-eocene or Post-miocene 
disturbances. On the contrary, they lie in hollows of denuda- 
ot shortly to be explained, of later date than these disturb- 
ces 
Fourthly, again, it may be supposed that the great lakes’ lie 
each in an area of special subsidence; but, in reply to this, it is 
evident that among the unnumbered lakes of Switzerland and 
talian Alps it would be easy to show a gradation in size, from 
the smallest tarn that lies in’ rock-basin to the Lakes of Geneva 
and Constance. Neither do I see any reason why mere size 
Should be considered the test of subsidence. Disallowing that 
test, we should require a great number of special subsidences, 
fach in the form of a rock-basin, in contiguous areas. Between 
» the Seidelhorn and Thun, for example, we should require one 
_ for the Todten See, several on the plateau on the north imme- 
