shelter from the storm. Presently he espied the low and narrow
entrance to what appeared to be a cave at the base of the cliffs
which formed the northern side of the gorge. With drawn knife he
approached the spot warily, for he knew that if it were a cave it
was doubtless the lair of some other beast. Before the entrance lay
many large fragments of rock of different sizes, similar to others
scattered along the entire base of the cliff, and it was in Tarzan's
mind that if he found the cave unoccupied he would barricade the
door and insure himself a quiet and peaceful night's repose within
the sheltered interior. Let the storm rage without-Tarzan would
remain within until it ceased, comfortable and dry. A tiny rivulet
of cold water trickled outward from the opening.

Close to the cave Tarzan kneeled and sniffed the ground. A low
growl escaped him and his upper lip curved to expose his fighting
fangs. "Numa!" he muttered; but he did not stop. Numa might not be
at home--he would investigate. The entrance was so low that the
ape-man was compelled to drop to all fours before he could poke
his head within the aperture; but first he looked, listened, and
sniffed in each direction at his rear--he would not be taken by
surprise from that quarter.

His first glance within the cave revealed a narrow tunnel with
daylight at its farther end. The interior of the tunnel was not so
dark but that the ape-man could readily see that it was untenanted
at present. Advancing cautiously he crawled toward the opposite
end imbued with a full realization of what it would mean if Numa
should suddenly enter the tunnel in front of him; but Numa did not
appear and the ape-man emerged at length into the open and stood
erect, finding himself in a rocky cleft whose precipitous walls