ut find it out--a history,
moreover, which instinct assured him would prove to be of the greatest
service to the Grenville search party at the present juncture. More, he
also knew for a fact that his friend Crewdson corresponded in cypher
with someone at Zanzibar, but even the cunning of Stanforth Kenyon had
totally failed to ascertain who that someone was, or by what name he or
she was designated, or, indeed, to get out of Master Crewdson Walworth
anything else at all worth knowing.

The detective, however, had put two and two together, and had built up a
theory in his usual cautious fashion, and every step of the ladder,
though most rigidly and thoroughly tested, had thus far proved to be
absolutely correct, and his deductions to be altogether justified by the
course of events.

CHAPTER TWO.

A NIGHT OF HORROR.

No serious mishap befell our pair of adventurers until they neared the
Katonga River, but just here they dropped in for a streak of ill-luck,
which was like to have brought the expedition to a premature and utterly
disastrous termination.

Leaving their men in camp one morning, Leigh and Kenyon had set out to
thoroughly and carefully explore a mighty kloof, or gorge, in the
adjacent hills, expecting to complete their investigations easily in a
couple of hours or thereabouts.

As the pair entered this natural mountain fastness, however, it rapidly
developed into a deep gorge, along which trickled a stream of water so
tiny that it frequently lost itself altogether amongst the stones which
served it for a bed.

On either hand great grey barren walls shot up like precipices, whilst
mighty scarped-out rocks seemed to hang over the very heads of the
explorers, the giant walls elsewhere being thickly fringed towards the
skyline with trees and bushes, many of the former absolutely hanging
head-downwards, and appearing to maintain their precarious tenure of
existence solely by the aid of magnificent festoons of creepers, which
hung from tree to rock, and from rock to tree, these gigantic parasites
absolutely sustaining the decayed trunks of many a long-dead monarch of
the woods, which they had enfolded in their tenacious and eventually
fatal embrace; higher still the foliage upon the very summit of the
cliffs looked like narrow gleaming threads of green and gold against the
dull background of soft sandstone rock. Within the kloof it was
unquestionably more or less dark at the best of times, but just now