clearly perceived. On so rugged a surface there was no means of
measuring the angle, but to give a common illustration, I may say that
the slope would not have checked the speed of an English mail-coach. In
some places, a continuous stream of these fragments followed up the
course of a valley, and even extended to the very crest of the hill. On
these crests huge masses, exceeding in dimensions any small building,
seemed to stand arrested in their headlong course: there, also, the
curved strata of the archways lay piled on each other, like the ruins
of some vast and ancient cathedral. In endeavouring to describe these
scenes of violence one is tempted to pass from one simile to another.
We may imagine that streams of white lava had flowed from many parts of
the mountains into the lower country, and that when solidified they had
been rent by some enormous convulsion into myriads of fragments. The
expression "streams of stones," which immediately occurred to every
one, conveys the same idea. These scenes are on the spot rendered more
striking by the contrast of the low rounded forms of the neighbouring
hills.
I was interested by finding on the highest peak of one range (about 700
feet above the sea) a great arched fragment, lying on its convex side,
or back downwards. Must we believe that it was fairly pitched up in
the air, and thus turned? Or, with more probability, that there
existed formerly a part of the same range more elevated than the point
on which this monument of a great convulsion of nature now lies. As
the fragments in the valleys are neither rounded nor the crevices
filled up with sand, we must infer that the period of violence was
subsequent to the land having been raised above the waters of the sea.
In a transverse section within these valleys, the bottom is nearly
level, or rises but very little towards either side. Hence the
fragments appear to have travelled from the head of the valley; but in
reality it seems more probable that they have been hurled down from the
nearest slopes; and that since, by a vibratory movement of overwhelming
force, [9] the fragments have been levelled into one continuous sheet.
If during the earthquake [10] which in 1835 overthrew Concepcion, in
Chile, it was thought wonderful that small bodies should have been
pitched a few inches from the ground, what must we say to a movement
which has caused fragments many tons in weight, to move onwards like so
much sand on a vibrating board, and find their level? I have seen, in
the Cordillera of the Andes, the evident marks where stupendous
mountains have been broken into pieces like so much thin crust, and the
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