by the
words of a man far more experienced than they in the deceitful ways of
the desert.

Before separating for the night, the three mids learnt from Bill and his
brother that the latter had been first officer of the ship that had
brought him to the coast. They could perceive by his conversation that
he was an intelligent man,--one whose natural abilities and artificial
acquirements were far superior to those of their shipmate,--the old
man-of-war's-man.

"If such an accomplished individual," reasoned they, "has been for ten
years a slave in the Saaera, unable to escape or reach any place where
his liberty might be restored, what hope is there for us?"

CHAPTER LXVII.

A LIVING STREAM.

Every hour of the journey presented some additional evidence that the
kafila was leaving the great desert behind, and drawing near a land that
might be considered fertile.

On the day after parting from the wreckers a walled town was reached,
and near it, on the sides of some of the hills, were seen growing a few
patches of barley.

At this place the caravan rested for the remainder of the day. The
camels and horses were furnished with a good supply of food, and water
drawn from deep wells. It was the best our adventurers had drunk since
being cast away on the African coast.

Next morning the journey was continued.

After they had been on the road about two hours, the old sheik and a
companion, riding in advance of the others, stopped before what seemed,
in the distance, a broad stream of water.

All hastened forward, and the Boy Slaves beheld a sight that filled them
with much surprise and considerable alarm. It was a stream,--a stream of
living creatures moving over the plain.

It was a migration of insects,--the famed locusts of Africa.

They were young ones,--not yet able to fly; and for some reason, unknown
perhaps even to themselves, they were taking this grand journey.

Their march seemed conducted in regular order, and under strict
discipline.

They formed a living moving belt of considerable breadth, the sides of
which appeared as straight as any line mathematical science could have
drawn.

Not one could be seen straggling from the main body, which was moving
along a track too narrow for their numbers,--scarce half of them having
room on the sand, while the other half were crawling along on the backs
of their _compagnons du voyage_.

Even the Arabs appeared interested in this African mystery, and