ic
shapes of the limestone pillars by which the vaulted roof was
supported. The whirring, fluttering, and twittering of many birds and
bats could plainly be heard in the larger caves, which were densely
peopled with winged and feathered inhabitants, and the roofs and sides
of which were blackened by their nests. The Segama River, which we had
ascended earlier, flows through these vast caverns, sometimes over a
hard, stony bottom, but oftener over or through a mass of guano many
feet in thickness, into which our guides more than once sank suddenly,
emerging in a state which can be better imagined than described. Split
palms were laid across the most awkward places; but it was extremely
difficult to keep one's footing on this primitive causeway, and
despite the assistance of the gentlemen, who carried me across many
of the streams, it was impossible to escape an occasional wetting.

At one point the guides and leading members of the party, going on
rather too rapidly, left us in complete darkness, and after waiting
some time in the hope that they would discover their mistake and
return, we had no alternative but to struggle up a most fearful
precipice towards the only ray of light which we could see in the
distance. It really was hard work, not only on account of the
steepness of the ascent, but of the slippery and slimy condition of
the rocks. Sometimes we knocked ourselves with painful abruptness
against hard projections, at other times we sank to our knees in a
mass of soft, wet guano teeming with animal life of various kinds, but
mostly of the biting or stinging character. Mr. Crocker slipped and
fell down some thirty feet or so, but fortunately emerged unhurt,
though covered with black slime from the crown of his head to the sole
of his foot.

After tremendous exertions we reached the end of our climb, during
which I had been not only once but many times sorely tempted, and even
strongly urged, to turn back. When we paused to rest, our eyes, by
this time accustomed to the dim religious light, could perceive human
figures crawling and clambering about the roof and pinnacles of the
vast cavern in which we now found ourselves, and could observe many
narrow rattan ladders hanging in the most precipitous places, or
stretching horizontally across almost unfathomable abysses.

Fixed among the rocks on every side were strong hooks and pegs, to
which the intrepid monkey-like nest-hunters attach their long,
swinging ladder