to
their arms, ammunition and matches, all of which had been most carefully
enveloped in mackintosh ground-sheets, himself proceeded to strike a
light. Now the striking of a match is a very trifling affair at
ordinary times, but, with a dark and doubtless vast unknown before them,
each waited anxiously to see what the tiny flame would reveal. One
brief instant it shed its feeble light upon their pallid faces, then, in
an endeavour to pierce the apparently limitless gloom, Grenville raised
the match above his head, and at that very moment there was a wild,
hissing rush, and the cavern stood revealed in a blinding glare of
light. The match had evidently ignited by accident a reservoir of
natural gas, and this, in the shape of an enormous stream of fire, now
hung globe-like from a rift in the roof of rock, where it arched a score
of feet above their heads.

One glance was sufficient to tell the merest novice in such matters that
this cavern had at some distant date formed the channel of one of those
underground rivers by no means uncommon in Africa. What had been the
bed of the stream was, however, filled in with earth, and was now to all
intents and purposes a very passable road, which, after mounting a short
hill that served in fact to keep back the water from the basin, ran
straight before them as far as the light could penetrate.

The first act of the whole party was to remove themselves from the
intense heat thrown out by the gas; their next, to draw their
pistol-cartridges and slip fresh ones into the chambers; and hardly was
this done when a startled exclamation, uttered just behind them, caused
all to turn hurriedly, only to find themselves confronted by a most
repulsive-looking white man, who stood dripping unpleasantly upon the
rocky ledge and regarding them with a scowling face.

The newcomer appeared altogether unarmed, and our friends promptly
rushed at him; but he incontinently turned tail, and dived out through
the entrance, followed like a flash of light by Myzukulwa.

The cousins waited in anxious suspense for close upon a minute, and then
the great Zulu silently appeared upon the rock and lay gasping for
breath. Soon, however, regaining his wind--

"Inkoos," he said, "he was too quick for me; the coward ran away down
the pass; but first he fired his gun, and it was answered by another gun
a mile away."

It was quite clear that the man had been a sentinel near to their old
sleeping-place, and,