See there already."

A slight dust had risen before the cliff. In the still air a few
grains of sand had begun to whirl round and round, with a speed which
increased to dizziness, giving us in advance the spectacle in
miniature of what would soon be breaking upon us.

With harsh cries a flock of wild geese appeared, flying low. They came
out of the west.

"They are fleeing towards the Sebkha d'Amanghor," said Bou-Djema.

There could be no greater mistake, I thought.

Morhange looked at me curiously.

"What must we do?" he asked.

"Mount our camels immediately, before they are completely
demoralized, and hurry to find shelter in some high places. Take
account of our situation. It is easy to follow the bed of a stream.
But within a quarter of an hour perhaps the storm will have burst.
Within a half hour a perfect torrent will be rushing here. On this
soil, which is almost impermeable, rain will roll like a pail of water
thrown on a bituminous pavement. No depth, all height. Look at this."

And I showed him, a dozen meters high, long hollow gouges, marks of
former erosions on the rocky wall.

"In an hour the waters will reach that height. Those are the marks of