There were seventy or eighty camels in all and ten mules, some of which carried Arab women who sat in the comfort born of habit, smoking pipes of the native tobacco.

First on the road were six camels, each carrying two children in what had been salt-panniers.

Marzuk, whose thongs had been loosened, and whose thirst had been assuaged, was but one of the twelve whom Hadj Abdullah had bought secretly or stolen, and, beyond the men engaged by him and the natives he had bribed, none knew aught of the camel’s freight.

Frightened as never in his life before, bruised and sickened by the camel’s irregular stride, his flesh scarred and his bones aching from the pressure of the raw hide thongs that had bound his limbs, faint for lack of food, and with nerves strained almost to breaking point, Marzuk was never in doubt about what had befallen him. He had been captured to be sold as a slave.

From the resting-place of the caravan the last camel had started on the road to Morocco, across eight hundred miles of desert, steering a north-north-westerly course over a track marked by the skeletons of men and beasts that had fallen by the way.

In her mud hut Aminah, never suspecting the truth, thought angrily and fearfully of the absent boy, and prayed that he might safely escape the hippopotami coming for their nightly prowl along the river banks.

As day succeeded day, other caravans arrived from the desert, but never a sign of the lad from the riverside came to relieve a mind grown weary now from anxiety and self-reproach. Weeks passed, and months, until Aminah knew that her prayers had failed to prevent evil spirits sacrificing her boy to the wild beasts of the river. And then she grew old suddenly, and within the year her place in the market was vacant.

Hadj Abdullah’s caravan made slow progress. The dwarf forest left behind, the sand waves of the Sahara stretched out before them, and in traversing this dry and burning sea the caravan endured days and weeks of travelling that taxed men and beasts to the uttermost.

Once a day, at sunset, the caravan halted, and then Marzuk and his eleven companions were taken from their panniers and fed. The Hadj feared to travel by starlight, save when forced to it by anticipation of an attack by the veiled brigands of the desert, lest the track should be missed.

Marzuk’s companion, a girl younger than himself, proved unable to endure the camel’s irregular stride, the scanty food, and the blinding sunlight. Before they had been two weeks on the road she could not eat. One morning she broke out into a fit of screaming that passed gradually into moans, and then stopped abruptly. In the evening, when the baskets were lowered, Hadj Abdullah was summoned in haste, but he could do no more than curse the man who had sold the child to him for half a bar of salt, and had sworn that she was sound and fit for the caravan journey. A little hole was scooped out in the sand; the tally of the caravan had been reduced by one. Next morning the burdens were rearranged, and Marzuk was carried in a basket with another lad, the camel that had carried him being requisitioned to carry one of the drivers who had fallen sick.