people are pleased to call Peruvian dew. That much rain does not fall
is very certain, for the houses are covered only with flat roofs made
of hardened mud; and on the mole shiploads of wheat were piled up,
being thus left for weeks together without any shelter.
I cannot say I liked the very little I saw of Peru: in summer, however,
it is said that the climate is much pleasanter. In all seasons, both
inhabitants and foreigners suffer from severe attacks of ague. This
disease is common on the whole coast of Peru, but is unknown in the
interior. The attacks of illness which arise from miasma never fail to
appear most mysterious. So difficult is it to judge from the aspect of
a country, whether or not it is healthy, that if a person had been told
to choose within the tropics a situation appearing favourable for
health, very probably he would have named this coast. The plain round
the outskirts of Callao is sparingly covered with a coarse grass, and
in some parts there are a few stagnant, though very small, pools of
water. The miasma, in all probability, arises from these: for the town
of Arica was similarly circumstanced, and its healthiness was much
improved by the drainage of some little pools. Miasma is not always
produced by a luxuriant vegetation with an ardent climate; for many
parts of Brazil, even where there are marshes and a rank vegetation,
are much more healthy than this sterile coast of Peru. The densest
forests in a temperate climate, as in Chiloe, do not seem in the
slightest degree to affect the healthy condition of the atmosphere.
The island of St. Jago, at the Cape de Verds, offers another strongly
marked instance of a country, which any one would have expected to find
most healthy, being very much the contrary. I have described the bare
and open plains as supporting, during a few weeks after the rainy
season, a thin vegetation, which directly withers away and dries up: at
this period the air appears to become quite poisonous; both natives and
foreigners often being affected with violent fevers. On the other hand,
the Galapagos Archipelago, in the Pacific, with a similar soil, and
periodically subject to the same process of vegetation, is perfectly
healthy. Humboldt has observed, that, "under the torrid zone, the
smallest marshes are the most dangerous, being surrounded, as at Vera
Cruz and Carthagena, with an arid and sandy soil, which raises the
temperature of the ambient air." [5] On the coast of Peru, however, the
temperature is not hot to any excessive degree; and perhaps in
consequence, the intermittent fevers are not of the most malignant
344