ter protective influence begins to establish
itself, the stones and waterfalls bounding away from the brow of the
precipice into the air, and wearing it at the top only. Also it is
evident that when the curvature falls into a vertical cliff, as
often happens, the maximum of curvature must be somewhere _above_
the brow of the cliff, as in the cliff itself it has again died into
a straight line.

[91] The following extract from my private diary, giving an account
of the destruction of the beauty of this waterfall in the year 1849,
which I happened to witness, may be interesting to those travellers
who remember it before that period. The house spoken of as
"Joseph's," is that of the guide Joseph Coutet, in a village about a
mile below the cascade, between it and the Arve: that noticed as of
the "old avalanche" is a hollow in the forest, cleft by a great
avalanche which fell from the Aiguille du Midi in the spring of
1844. It struck down about a thousand full-grown pines, and left an
open track in the midst of the wood, from the cascade nearly down to
the village.

"Evening, Thursday, June 28th. I set out for the Cascade des
Pelerins as usual; when we reached Joseph's house, we heard a sound
from the torrent like low thunder, or like that of a more distant
and heavier fall. A peasant said something to Joseph, who stopped to
listen, then nodded, and said to me, 'La cascade vient de se
deborder.' Thinking there would be time enough afterwards to ask for
explanations, I pushed up the hill almost without asking a question.
When we reached the place of the old avalanche, Joseph called to me
to stop and see the torrent increase. There was at this time a dark
cloud on the Aiguille du Midi, down to its base; the upper part of
the torrent was brown, the lower white, not larger than usual. The
brown part came down, I thought, with exceeding slowness, reaching
the cascade gradually; as it did so, the fall rose to about once and
a half its usual height, and in the five minutes' time that I paused
(it could not be more) turned to the color of slate. I then pushed
on as hard as I could. When I reached the last ascent I was obliged
to stop for breath, but got up before the fall could sensibly have
diminished in body of water. It was then nearly twice as far cast
out from the rock as last night, and