called a grand valley), that its bed, though composed merely of sand
and gravel, was higher than that of its tributary. A mere rivulet of
water, in the course of an hour, would have cut a channel for itself;
but it was evident that ages had passed away, and no such rivulet had
drained this great tributary. It was curious to behold the machinery,
if such a term may be used, for the drainage, all, with the last
trifling exception, perfect, yet without any signs of action. Every
one must have remarked how mud-banks, left by the retiring tide,
imitate in miniature a country with hill and dale; and here we have the
original model in rock, formed as the continent rose during the secular
retirement of the ocean, instead of during the ebbing and flowing of
the tides. If a shower of rain falls on the mud-bank, when left dry,
it deepens the already-formed shallow lines of excavation; and so it is
with the rain of successive centuries on the bank of rock and soil,
which we call a continent.
We rode on after it was dark, till we reached a side ravine with a
small well, called "Agua amarga." The water deserved its name, for
besides being saline it was most offensively putrid and bitter; so that
we could not force ourselves to drink either tea or mate. I suppose
the distance from the river of Copiapo to this spot was at least
twenty-five or thirty English miles; in the whole space there was not a
single drop of water, the country deserving the name of desert in the
strictest sense. Yet about half way we passed some old Indian ruins
near Punta Gorda: I noticed also in front of some of the valleys, which
branch off from the Despoblado, two piles of stones placed a little way
apart, and directed so as to point up the mouths of these small
valleys. My companions knew nothing about them, and only answered my
queries by their imperturbable "quien sabe?"
I observed Indian ruins in several parts of the Cordillera: the most
perfect which I saw, were the Ruinas de Tambillos, in the Uspallata
Pass. Small square rooms were there huddled together in separate
groups: some of the doorways were yet standing; they were formed by a
cross slab of stone only about three feet high. Ulloa has remarked on
the lowness of the doors in the ancient Peruvian dwellings. These
houses, when perfect, must have been capable of containing a
considerable number of persons. Tradition says, that they were used as
halting-places for the Incas, when they crossed the mountains. Traces
of Indian habitations have been discovered in many other parts, where
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