some time after they had
finally lost touch with the river and had got away from the vast plains
on to higher ground, where the forest was less dense, the undergrowth
much thinner--becoming in some places altogether non-existent--and where
open glades became increasingly frequent and of ever extending area.

Thus far the travellers had met with no very remarkable experiences.
There is nothing exciting in the work of hewing a path for oneself
through miles of tough, tangled undergrowth, or in toiling thirstily
hour after hour in sweltering heat, wondering meanwhile how much longer
it will be before the welcome sound of trickling water will reach one's
ears; even crouching in concealment for hours at a stretch, rifle in
hand, in the hope that something eatable will come within shot, soon
grows monotonous; while, as for the multitudinous nocturnal sounds of
the forest, so weird and thrilling when first heard, the party soon
became accustomed to them, and slept soundly through them all.

But, naturally, in the course of a long journey through the unexplored
wilds of South America, interesting incidents are by no means uncommon,
while others of a more weird and thrilling character occur occasionally,
as our friends were to learn in due time. It was, however, one of the
merely interesting kind that awaited them in an open glade which they
entered on a certain evening, after a long and toilsome journey, just as
the sun's last rays were gilding the tree-tops on the eastern side of
the clearing.

The weary, sweat-drenched travellers celebrated their arrival in this
wide open space with shouts of joy, for a tiny streamlet meandered
through the middle of it, while in other respects it was ideal, not only
as a camping place for the coming night, but also as a spot upon which
to halt and recuperate for a few days--a relaxation which they had been
promising themselves during the past fortnight. It was the bone-weary
Indian carriers who were loudest in the expression of their rejoicing as
they stumbled through the tangled grass toward the margin of the tiny
stream, upon the bank of which their camp would be pitched; and as they
gladly flung down their burdens on the chosen spot, they emitted a final
yell of satisfaction which, to the astonishment of all, was answered,
from some distance on the opposite side of the stream, by a wailing cry,
as of some person--or, more probably, some creature--in extreme anguish.
The cry was so pecu