in Europe and North America. 329 
proved by the contortion of the Miocene strata, as for instance 
in the neighborhood of Lucerne, where, on the Rigi (and in 
other conglomeratic mountains on the same strike), the strata 
are considered by the best Swiss geologists to be repeatedly 
folded and fairly inverted, so that the basement-beds form the 
p of the mountain, instead of its bottom, thus, by reversal of 
dip, plunging under the Eocene and Cretaceous strata of the 
mountains further south. The whole, as shown by the rapid 
truncated folding and the escarpments of the hills, has since 
been much denuded, the denudation being of a kind and amount 
that, to effect it, proves the lapse of a long period of time. 
Witness the outliers of Miocene strata in the upland valleys of 
€Jura. Among these disturbed and denuded strata of Mio- 
ene and of older dates, the Lakes of Geneva, Thun, Brienz, 
Lucerne, Zurich, Constance, the Wallen See, and the great lakes 
of north Italy lie. A knowledge of the stratigraphical structure 
of the Alps, in my opinion, proves that these lakes do not lie 
among the strata in basins merely produced by disturbance of 
the rocks, but in hollows due to denuding agencies that operated 
long after the complicated foldings of the Miocene and other 
strata were vasidaaerh 
Country took place. The only approach to this may ibly 
be in the td valleys of the Jura, where a part of the Sova 
beds lie in basins separated by secondary anticlinally curved 
Strata, 
denudation ; but these cases are surrounded with difficulties, 
The lake-hollows in the Alps are, however, encircled by rocks, 
ance. The fragmentary state of the uppermost Miocene strata 
of the iowiande-ct Seimestland proves this denudation. Again, 
it be argued that in the lake-areas these denudations have 
———— by the waters of the lakes, it is replied that, 
though waves may form cliffs, neither running nor still water 
can se out deep trough-shaped hollows. _ 
Secondly, the same kind of argument applies to areas of mere 
Watery erosion by rivers. Running water may scoop outa 
