Truxillo, Guayaquil, Panama, or Cartagena. The difficulty of respiration,
called in some places _la puna_, and in others _el siroche_,
experienced in those parts of the Andes which most abound in metals, was
so great at times, that, whilst on the march, whole battalions would sink
down, as if by magic, and it would have been inflicting death to have
attempted to oblige them to proceed until they had rested and recovered
themselves. In many cases life was solely preserved by opening the
temporal artery. This sudden difficulty of respiration is supposed to be
caused by occasional exhalations of metalliferous vapour, which, being
inhaled into the lungs, causes a strong feeling of suffocation.

During certain months of the year, tremendous hail-storms occur. They have
fallen with such violence that the army has been obliged to halt, and the
men being compelled to hold up their knapsacks to protect their faces,
have had their hands so severely bruised and cut by large hail-stones as
to bleed copiously.

Thunder-storms are also particularly severe in the elevated regions. The
electric fluid is seen to fall around, in a manner unknown in other parts
of the world, and frequently causes loss of life. Such storms have often
burst at some distance below their feet, as the army climbed the lofty
ridges of the Andes.

The distressing fatigues of the most difficult marches in Europe cannot
perhaps be compared to those which the patriot soldiers underwent in the
campaign of 1824. From Caxamarca (memorable for the seizure and death of
Atuhualpa) to Cuzco, the whole line of the road (with the exception of the
plain between Pasco and the vicinity of Tarma, twenty leagues in extent,
and the valley of Xauxa) presents a continuation of rugged and fatiguing
ascents and declivities. That these difficulties do not diminish between