hich they passed. We have, moreover, on the plains at the feet
of the mountains, and in enormous quantities, the very matter derived
from the sculpture of the mountains themselves.

The plains of Italy and Switzerland are cumbered by the _debris_ of the
Alps. The lower, wider, and more level valleys are also filled to
unknown depths with the materials derived from the higher ones. In
the vast quantities of moraine-matter which cumber many even of the
higher valleys we have also suggestions as to the magnitude of the
erosion which has taken place. This moraine-matter, moreover, can
only in small part have been derived from the falling of rocks upon
the ancient glacier; it is in great part derived from the grinding and
the ploughing-out of the glacier itself. This accounts for the
magnitude of many of the ancient moraines, which date from a period
when almost all the mountains were covered with ice and snow, and
when, consequently, the quantity of moraine-matter derived from the
naked crests cannot have been considerable.

The erosion theory ascribes the formation of Alpine valleys to the
agencies here briefly referred to. It invokes nothing but true
causes. Its artificers are still there, though, it may be, in
diminished strength; and if they are granted sufficient time, it is
demonstrable that they are competent to produce the effects ascribed
to them. And what does the fracture theory offer in comparison? From
no possible application of this theory, pure and simple, can we obtain
the slopes and forms of the mountains. Erosion must in the long run
be invoked, and its power therefore conceded. The fracture theory
infers from the disturbances of the Alps the existence of fissures;
and this is a probable inference. But that they were of a magnitude
sufficient to produce the conformation of the Alps, and that they
followed, as the Alpine valleys do, the lines of natural drainage of
the country, are assumptions which do not appear to me to be justified
either by reason or by observation.

There is a grandeur in the secular integration of small effects
implied by the theory of erosion almost superior to that involved in
the idea of a cataclysm. Think of the ages which must have been
consumed in the execution of this colossal sculpture. The question
may, of course, be pushed further. Think of the ages which the molten
earth required for its consolidation. But these vaster epochs lack
sublimity through our in