the
right is merely a perspective line, the part of the contour _c d_, Fig.
33, p. 181, which literally overhangs,[82] cannot be. An apparent slope,
however steep, so that it does not overpass the vertical, _may_ be a
horizontal line; but the moment it can be shown literally to overhang,
it _must_ be one of two things,--either an actually pendant _face_ of
rock, as at _a_, Fig. 77, or the under edge of an overhanging _cornice_
of rock, _b_. Of course the latter condition, on such a scale as this of
the Matterhorn, would be the more wonderful of the two; but I was
anxious to determine which of these it really was.

[Illustration: 38. The Cervin, from the East and North-east.]

Sec. 8. My first object was to reach some spot commanding, as nearly as
might be, the lateral profile of the Mont Cervin. The most available
point for this purpose was the top of the Riffelhorn; which, however,
first attempting to climb by its deceitful western side, and being
stopped, for the moment, by the singular moat and wall which defend its
Malakhoff-like summit, fearing that I might not be able ultimately to
reach the top, I made the drawing of the Cervin, on the left hand in
Plate +38+, from the edge of the moat; and found afterwards the
difference in aspect, as it was seen from the true summit, so slight as
not to necessitate the trouble of making another drawing.[83]

[Illustration: FIG. 78.]

[Illustration: FIG. 79.]

Sec. 9. It may be noted in passing, that this wall which with its regular
fosse defends the Riffelhorn on its western side, and a similar one on
its eastern side, though neither of them of any considerable height, are
curious instances of trenchant precipice, formed, I suppose, by slight
slips or faults of the serpentine rock. The summit of the horn, _a_,
Fig. 78, seems to have been pushed up in a mass beyond the rest of the
ridge, or else the rest of the ridge to have dropped from it on each
side, at _b c_, leaving the two troublesome faces of cliff right across
the crag, hard, green as a sea wave, and polished like the inside of a
seashell, where the weather has not effaced the surface produced by the
slip. It is only by getting past the eastern cliff that the summit can
be reached at all, for on its two lateral escarpments the mountain seems
quite inaccessible, being in its whole mass nothing else than the top of
a narrow wall with a raised battlement, as rudely shown in perspective
at _e d_; the flanks of the wal