on discovering him at the termination of his round, was to utter the
word "_Akka_" so that the sailor should distinguish him from an enemy.

The Arabs themselves were supposed to be sufficiently intelligent to
tell a friend from a foe without requiring any countersign.

Before Bill was sent upon his beat the old sheik went into a tent, and
soon after reappeared with a large pistol, bearing a strong likeness to
a blunderbuss. This weapon he placed in the sailor's hand, with the
injunction, translated to him by the interpreter, not to discharge it
until he should be certain of killing either Golah, or one of his
companions.

The old sailor, although sorely fatigued with the toil of the day's
journey, had so great a horror of again becoming the property of the
black sheik, that he cheerfully promised to "walk the deck all night,
and keep a good look-out for breakers," and his young companions sought
repose in full confidence that the promise would be faithfully kept.

Any one of the boy slaves would willingly have taken his place, and
allowed their old comrade to rest for the night, but Bill had been
selected by the old sheik, and from his decree there was no appeal.

The two Arabs doing duty as sentinels knew, from past experience, that
if the kafila was still followed by Golah, they would be the individuals
most exposed to danger, and this knowledge was sufficient to stimulate
them to the most faithful discharge of their trust.

Neither of them wished to become victims to the fate which had befallen
their predecessors in office.

For two or three hours both paced slowly to and fro; and Bill, each time
he approached the end of his beat, could hear distinctly pronounced the
word "_Akka_" which proved that his co-sentinels were fully on the
alert.

It so chanced that one of them had no faith in the general belief that
the enemy had relinquished his sanguinary purposes of vengeance.

He drew his deductions from Golah's conduct in the past, and during the
long silent hours of the night his fancy was constantly dwelling on the
manner in which the dreaded enemy had approached the _douar_ on former
occasions.

This sentry was the one stationed to the south of the _douar_; and with
eyes constantly striving to pierce the darkness that shrouded the
sand-plain, the water, on which a better light was reflected, received
no attention from him. He believed the _douar_ well protected on the
side of the sea, for he had no i