nest blasts, there was less thunder in it, and
more high-pitched horn-like music, but the effect was electrical.

There was an echo in that valley, and this echo took up the sound,
repeated it, and seemed to send it on to a signalling station higher up,
where it was caught and sent on again, and then again and again, each
repetition growing weaker and softer than the last.

But only one of these echoes was heard by the travellers, for, as afore
said, the effect was electrical.

The moment that blast was blown behind him, Ali Baba, Lawrence's
cream-coloured horse, threw up his head, then lowered it, and lifted his
heels, sending his rider nearly out of his saddle, uttered a peculiar
squeal, and set off at a gallop.

The squeal and the noise of the hoofs acted like magic upon the other
three horses, and away they went, all four as hard as they could go at
full gallop, utterly regardless of the pulling and tugging that went on
at their bits.

This wild stampede went on along the valley for quite a quarter of an
hour before Yussuf was able to check his steed's headlong career; and it
was none too soon, for the smooth track along the valley was rapidly
giving way to a steep descent strewed with blocks of limestone, and to
have attempted to gallop down there must have resulted in a serious
fall.

As it was, Yussuf was only a few yards from a great mass of rock when
his hard-mouthed steed was checked; and as the squeal of one had been
sufficient to start the others, who had all their early lives been
accustomed to run together in a drove, so the stopping of one had the
effect of checking the rest, and they stood together shaking their ears
and pawing the ground.

As soon as he could get his breath, Lawrence began to laugh, and Mr
Preston followed his lead, while the grave Muslim could not forbear a
smile at Mr Burne. This worthy's straw hat had been flying behind,
hanging from his neck by a lanyard, while he stood up in his stirrups,
craned his neck forward, and held his pocket-handkerchief whip fashion,
though it more resembled an orange streak of light as it streamed
behind; while now, as soon as the horse had stopped, he climbed out of
the saddle, walked two or three steps, and then sat down and stared as
if he had been startled out of his senses.

"Not hurt, I hope, Burne," said the professor kindly.

"Hurt, sir--hurt? Why, that brute must be mad. He literally flew with
me, and I might as well have pulled at