Quickly the attackers discharged their weapons; then, having done all that could be done, lay prone and waited.
Once again that hollow moaning sound drifted in across the baked expanse of the Sahara--a strange, empty sound, unreal and ominous.
Then came a stir of sultry breeze, from the east.

It strengthened; and a fine, crepitant sliding of sand-particles became audible.

Rrisa stirred uneasily.
"Master," he whispered, "we should not delay.

If the _jinnee_ of the waste overtake us, we may be lost." "The _jinnee_ of the waste ?" the Master answered, in a low tone.

"What nonsense is this ?" "The simoom, Master--the storm of sand.