like a hole than a valley, for there was no way in or out,'" quoted
Sellon again. "Now, you would hardly find such a formation at the
bottom of a mountain--though you very conceivably might at the top."

"But I tell you there can't be room for such a thing at the top of that
cock's-comb," objected Renshaw, dubiously. "I've been all round the
mountain more than once, and it's narrow at the top."

"Maybe. On the other hand, it may not be so narrow as you think. A
mountain is the devil for changing its shape from whatever point you
look at it--almost in whatever light or shade. Then, again, Greenway
may have exaggerated the size of the hole. I tell you what it is,
Fanning old chap. I believe I've solved the riddle that has been
besting you all these years. As you said when we first talked the
affair over, `two heads are better than one--even donkeys' heads,'
There's a third head, and that's the head of the `right nail,' and I
believe we've hit it. Saddle up."

"Don't be too sanguine, Sellon. You'll be doubly sold if your idea ends
in smoke."

They were not long in reaching the mountain referred to. It was of
conical formation and flat-topped. But from one end of its table-like
summit rose a precipitous, razor-backed ridge--serrated and on its
broader side taking the shape of a cock's-comb.

Though steep and in parts rugged, the ascent was easy; indeed, it seemed
likely they could ride to the very summit. Renshaw eyeing the towering
slope, shook his head.

"It's rough on the horses," he said. "They haven't got any superfluous
energy at this stage of the proceedings, and that berg can't stand much
under three thousand feet. Still they've got to go with us. If we left
them down here they might be jumped; and then, again, if your idea
should be the right one, we might be days up there. I only hope we
shall find water, anyhow."

CHAPTER TWENTY EIGHT.

"IT IS A WHITE MAN'S SKULL."

It was, as Renshaw had put it, "rough on the horses." But the colonial
horse, in contrast to his English brother, is pre-eminently an animal
for use, and not for show and the primary object of supporting a crowd
of stable hands. So puffing and panting, stumbling a little here and
there, the poor beasts gallantly breasted the grassy steep in the wake
of their masters, who had elected to spare their steeds by leading
instead of riding them.

"The mountain certainly is built on a larger scale than one would think
from