"Near to that mule!" interrupted Charnock. "And he was the richest man in all Tangier."

A moment later there was shown to him the second picture which he was to carry away from Tangier. Down the Sôk, through the crowd, came the Moor, in his spotless robes, and a few yards behind him, striding swiftly and noiselessly, the blind gaunt beggar of the cemetery gate followed upon his trail. In and out amongst the shifting groups he threaded and wound, and never erred in his pursuit. The man in whose track he kept never spoke when all were shouting, yet Hassan never faltered. The sound of his footsteps was lost in a multitude of the like sounds, yet Hassan was somehow sensible of it, somehow to his ears it emerged distinct.

Charnock was amazed; in a way too he was chilled. It seemed uncanny that this sightless creature of the impassive face should be able to follow, follow, follow relentlessly, unswervingly, one silent man amongst the noisy hundreds. Charnock walked for a few yards by Hassan Akbar's side, keeping pace with him. Even with his eyes fixed upon the Moor in front, even though he saw his feet tread the ground, he could not distinguish his footfalls. How then could Hassan?

Tracker and Tracked passed from the Sôk under the archway of the gate, and Charnock dismissing Hamet walked down towards his hotel near the waterside. However, he missed his road. He turned through the horse market, descended the steep street, past the great Mosque, and walked along a narrow, crooked alley between blank and yellow walls, which ended in a tunnel beneath over-arching houses. Almost within the mouth of this tunnel there was a shop, or so it seemed, for a stuffed jackal swung above the door as a sign. Before this shop Charnock halted with a thrill of excitement. The door of the shop was shut, the unglazed window was shuttered. It was not on that account that Charnock stopped; but underneath the shuttered window, his head almost touching the sill, Hassan squatted on the cobbles fingering now and then a silver dollar.

Inside the door a bolt grated, the door opened, and a stout, undersized European appeared in the entrance, polished a pair of glasses, set them upon his nose, glanced up and down the street, closed the door behind him, and taking no heed whatever of the blind man under his window, walked briskly into the tunnel. He walked with a short, tripping, and jaunty step.

Charnock waited while the echo of it diminished and ceased, and the moment it had ceased he saw Hassan, without any hurry, without any sign of expectation or excitement, rise slowly to his feet and move along the house wall towards the door. His right elbow scraped the plaster; then his elbow touched nothing. He had come to the recess of the door, and he stopped.

It flashed upon Charnock that he had not heard the bolt again grate into its socket. The door was then only latched and--was Hassan's quarry behind its panels?

The affair had ceased to be a toy with which Charnock's imagination could idly play. He strode across the alley and planted himself face to face with Hassan. Hassan quietly and immediately murmured a request for alms and stretched out his left hand, a supple, corded hand, with long sinuous fingers, a hand of great strength. But as he spoke he drew within the recess of the door, and Charnock noticed his right hand steal up the panels feeling for the latch.

Made by this seemingly passionless and apathetic man, the secret movement shocked Charnock. It seemed to him at that moment so cold-blooded as to be almost inhuman.

"Look out!" he shouted through the door and in broad English, forgetting that the man for whom his warning was intended was a Moor. But the warning had its effect. There was a heavy blow upon the door, as though a man's shoulder lurched against it, and then the bolt grated into the socket. Hassan Akbar walked on repeating his prayer for alms, as if his hand had never for an instant stolen up the panel and felt for the latch.