motion, however,
inspired no sense of danger.

We carefully measured the length and altitude of the bridge, and found
it to be from fastening to fastening one hundred and forty-eight feet
long, and at its lowest part one hundred and eighteen feet above the
river. Mr. Markham, who crossed it in 1855, estimated the length at
ninety feet and the height at three hundred feet. Lieutenant Gibbon,
who crossed it in 1857, estimated the length at three hundred and
twenty-four feet and the height one hundred and fifty feet. Our
measurements, however, are exact. The height may be increased perhaps
ten feet when the cables are made taut. They are five in number, twisted
from the fibres of the _cabuya_, or maguey plant, and are about four
inches thick. The floor is of small sticks and canes, fastened
transversely with raw-hide strings. The Indians coming from Andahuaylas
and other districts where the cabuya grows, generally bring a quantity
of leaves with them wherewith to pay their toll. These are prepared and
made into rope by the custodians of the bridge, who must be glad of some
occupation in their lone and lofty eyrie.

Our baggage was carried over the bridge, and the animals were then
led across one by one, loaded and started up the mountain. The space
is too limited to receive more than two loaded mules at a time, and
instances are known of their having been toppled over the precipice
from overcrowding. We led our horses over without difficulty except in
getting them on the bridge. But once fairly on the swaying structure
they were as composed as if moving on the solid ground. Perhaps even to
the lowest animal intelligence it must be apparent that the centre of
the bridge of the Apurimac is not the place for antics, equine or
asinine.

Mounted once more, we commenced our steep and difficult ascent. At one
place the sheer precipice presented itself on one side, and a vertical
wall on the other; next it was a scramble up a ladder of stairs, partly
cut in the rock and partly built up with stones against it; then a
sudden turn, with a parapet built around it in a semi-circle, to prevent
descending animals from being carried into the abyss below by their own
momentum. Our cargo-mules toiled up painfully above us, stopping every
few steps to breathe, while the muleteers braced themselves against
their haunches to afford them some support and rest.

We had scarcely reached half-way to the mouth of the tunnel, which
enters the m