er, and we do
not perceive the place from whence that repairing matter had proceeded.
Therefore, that which here appears does not immediately suggest to the
spectator what had been the state of things before the valley had been
hollowed out, or before that plain, through which the river runs so
naturally as being in the lowest place, was made. But it is otherwise in
the valley of the rivulet; no person can examine this subject without
seeing that the rivulet carries away matter which cannot be repaired
except by wearing away some part of the mountain, or the surface of that
place upon which the rain, which forms the stream, is gathered. In those
rivulets, or their little plains, we see the detached parts remaining
in the soil, and also the place from whence those detached parts were
taken. Here we need no long chain of reasoning from effect to cause;
the whole operation is in a manner before our eyes. In this case, it
requires but little study to replace the removed parts; and thus to see
the work of nature, resolving the most hard and solid masses by the
continued influences of the sun and atmosphere. In this state of things,
we are easily made to understand how heavy bodies are travelled along
the declivity of the earth, by means of water running from the height.

Such is the system of rivers and their valleys; nor is there upon the
continent a spot on which some river has not run. But, in the Alps of
Switzerland and Savoy, there is another system of valleys, above that
of the rivers, and connected with it. These are valleys of moving ice,
instead of water. This icy valley is also found branching from a greater
to a lesser, until at last it ends upon the summit of a mountain,
covered continually with snow. The motion of things in those icy valleys
is commonly exceeding slow, the operation however of protruding bodies,
as well as that of fracture and attrition, is extremely powerful.

To illustrate those operations of excavating the valleys of rivers and
of thus undermining mountains which fall by their proper weight, I shall
transcribe some descriptions of what is to be found among the Alps. But
first I would wish to carry my reader to the summit of that country, to
examine the state of that part which nothing can have affected but the
immediate influences of the sun and air. After having thus formed some
idea of the summit of this wasting country, we shall next examine the
valleys through which the materials of the d