ut of a block of nearly
horizontal beds of gneiss. But in all these cases the materials are so
hardened and knit together that to all intents and purposes they form
one solid mass, and when the forms are to be of the boldest character
possible, this solid mass is unstratified, and of compact crystalline
rock.

Sec. 6. In looking from Geneva in the morning light, when Mont Blanc and
its companion hills are seen dark against the dawn, almost every
traveller must have been struck by the notable range of jagged peaks
which bound the horizon immediately to the north-east of Mont Blanc. In
ordinary weather they appear a single chain, but if any clouds or mists
happen to float into the heart of the group, it divides itself into two
ranges, lower and higher, as in Fig. 1, Plate 29, of which the uppermost
and more distant chain is the real crest of the Alps, and the lower and
darker line is composed of subordinate peaks which form the south side
of the valley of Chamouni, and are therefore ordinarily known as the
"Aiguilles of Chamouni."

[Illustration: J. Ruskin. J.C. Armytage
29. Aiguille Structure.]

Though separated by some eight or nine miles of actual distance, the two
ranges are part of one and the same system of rock. They are both of
them most notable examples of the structure of the compact crystalline
peaks, and their jagged and spiry outlines are rendered still more
remarkable in any view obtained of them in the immediate neighborhood of
Geneva, by their rising, as in the figure, over two long slopes of
comparatively flattish mountain. The highest of these is the back of a
stratified limestone range, distant about twenty-five miles, whose
precipitous extremity, nodding over the little village of St. Martin's,
is well known under the name of the Aiguille de Varens. The nearer line
is the edge of another limestone mountain, called the Petit Saleve,
within five miles of Geneva. And thus we have two ranges of the
crystalline rocks opposed to two ranges of the coherents, both having
their distinctive characters, the one of vertical fracture, the other of
level continuousness, developed on an enormous scale. I am aware of no
other view in Europe where the essential characteristics of the two
formations are so closely and graphically displayed.

Sec. 7. Nor can I imagine any person thoughtfully regarding the more
distant range, without feeling his curiosity strongly excited as to the
method of its fi