f the glacier, and the streaks which vary more or less from this
direction are produced by the local effects of oscillation and retreat,
as we shall presently see.

"4. The Lapiaz, or Lapiz, which the inhabitants of German Switzerland
call Karrenfelder, cannot always be distinguished from erosions,
because, both produced as they are by water, they do not differ in their
exterior characteristics, but only in their positions. Erosions due to
torrents are always found in places more or less depressed, and never
occur upon large inclined surfaces. The Lapiaz, on the contrary, are
frequently found upon the projecting parts of the sides of valleys in
places where it is not possible to suppose that water has ever formed
a current. Some geologists, in their embarrassment to explain these
phenomena, have supposed that they were due to the infiltration of
acidulated water, but this hypothesis is purely gratuitous.

"We will now describe the remains of these various phenomena as they are
found in the Alps outside the actual glacial limits, in order to prove
that at a certain epoch glaciers were much larger than they are to-day.

"The ancient moraines, situated as they are at a great distance from
those of the present day, are nowhere so distinct or so frequent as
in Valais, where MM. Venetz and J. de Charpentier noticed them for the
first time; but as their observations are as yet unpublished, and they
themselves gave me the information, it would be an appropriation of
their discovery if I were to describe them here in detail. I will limit
myself to say that there can be found traces, more or less distinct, of
ancient terminal moraines in the form of vaulted dikes at the foot of
every glacier, at a distance of a few minutes' walk, a quarter of an
hour, a half-hour, an hour, and even of several leagues from their
present extremities. These traces become less distinct in proportion
to their distance from the glacier, and, since they are also often
traversed by torrents, they are not as continuous as the moraines which
are nearer to the glaciers. The farther these ancient moraines are
removed from the termination of a glacier, the higher up they reach upon
the sides of the valley, which proves to us that the thickness of the
glacier must have been greater when its size was larger. At the same
time, their number indicates so many stopping-places in the retreat of
the glacier, or so many extreme limits of its extension--limits which