narrow passages.

In the neighbourhood of Valparaiso, above which Aconcagua (23,000 feet
in height) looks down on the Pampas on one side and the blue Pacific on
the other, is the beautiful valley of Guillota, thoroughly irrigated and
brought under cultivation. It has, during the whole summer, the hot sun
striking down from a cloudless sky. It is only in these parts where the
nature of the streams affords means of irrigation that vegetation can
exist.

Further north, the western shore is in many parts very arid; and about
latitude 20 degrees south the burning desert commences, extending 540
leagues--almost to the Gulf of Guayaquil--and varying in width from
three to twenty leagues. Over this region of death, heaps of stone or
mounds of sand are alone seen, except where, at wide intervals, some
mountain stream, fed by the melting snows of the lofty peaks, finds its
way into the ocean. It is only in the neighbourhood of these rivers
that man can venture to take up his abode. On the banks of most of them
have been built the few cities which exist near the sea in Peru. For
some miles the traveller finds not a drop of water, no trace of
vegetation. His weary horse sinks, overcome with the pangs of thirst
and the fatigue of dragging its limbs through the soft sand. Through
this region the mule can alone be trusted, as, like the camel of the
Eastern desert, it will longer endure fatigue and want of water. Here,
as in the deserts of Africa, violent winds stir up the sand, forming
vast columns, as terrible in their effects as the flames of the prairie.
Rising to a hundred feet in height, they are seen approaching, whirling
through the air, till the unhappy traveller finds himself surrounded by
an overwhelming mass, and, unable to breathe, sinks exhausted on the
ground. Flight alone can save him. Many have here perished. On
several occasions, troops attempting to cross the desert have been
overwhelmed. Others have lost their way when traversing the sandy
plains, and have wandered about, in vain seeking for water to quench
their burning thirst. On one side is the salt ocean, on the other the
rocky precipices of the mountains. Wandering on for hours and hours, at
length, exhausted, they have abandoned themselves to despair. These
sand-storms occur more especially during the heats of summer, so
completely altering the appearance of the country, by covering it with
large hillocks, that the most experienced guides fin