nt, misfortune had overtaken our two
friends since we saw them last. While riding along the burning sandy
bottom of a dreary defile towards evening, the led horse had
inadvertently trodden on a puff-adder--which, sluggish brute that it is,
rarely gets out of the way. Blowing himself out with rage, this hideous
reptile had flung up his squat bloated length, fastening his fangs in
the leg of the unfortunate horse. The animal was doomed, and, indeed,
in less than an hour was in its expiring throes.

Now, this was a terrible misfortune, for not only was the climbing and
digging gear among the pack-load, but also the water-skin, and by far
the greater part of their provisions; nearly the whole of the latter had
to be abandoned, and loading up all that was indispensable upon their
riding horses--already fast losing their former freshness--the two
adventurers had pushed on. But by now the contents of the water-skin
had run very low indeed; were it not for the lucky find of a tiny pool
of slimy fetid water standing in a cavity of a rock, the horses would
have given out already. As it was, they drank it up every drop, and
felt the better for it.

"I doubt whether that bag of bones will carry me back, as it is," said
Sellon, gloomily, eyeing his dejected steed, now too weary to graze.

"Sellon," said Renshaw, earnestly, still gazing around and completely
ignoring his companion's last remark--"Sellon, I can't make it out now
any more than the first time I was here. We have followed out the clue
most minutely: `Straight from the smaller turret-head, facing the
setting sun. Within a day's ride.' Now, we have explored and surveyed
every point westerly between north and south, and within a good deal
more than a day's ride, thoroughly and exhaustively. There isn't the
shadow of a trace of any such valley, or rather crater, as old Greenway
describes. But let's go over the thing carefully again."

Suddenly Maurice sat up from his weary lounging attitude.

"By Jove, Fanning, but you've given me an idea," he said, speaking
eagerly and quickly.

"One moment," said Renshaw, holding up his hand. "I have an idea, too,
and indeed it's astonishing it should never have struck me before. You
must remember old Greenway was talking very disjointedly at the end of
his yarn--poor old chap. He was nearly played out. Well, I tried to
take down his words exactly as he uttered them. Look at this `Straight
from--the smaller one--facing