They were passing now through a strange, open space, between old arches that for an instant arrested his excavator’s interest.  He saw in the shadows about them, a crumpled, crumbling dome and broken shafts, with half a wall of masonry pierced with Arabesques.  Traces of old ruins, fragments of some old, forgotten mosque over which the palace had spread its foundations in bygone days....  Buried treasure, looted, some of it, for the palace overhead, but still rare and lovely....  That was a gleam of lapis lazuli that winked at him from the crumbling mortar under his feet.

Then they were between other walls, not crumbling ones, but the solid, pillared blocks of the palace masonry with here and there broad arches of old brick.

They stopped.  Between two arches the general held his lantern high, flashing it over the surface while Yussuf swung down his sack and knocked with the handle of his tool.

Suddenly he stopped and looked at his master, nodding cheerfully.  The general lowered his light and stepped back and Yussuf reared the pickaxe in his powerful arms and sent it dexterously at the wall, between two broken bits of brick.

It caught, and sent the mortar spraying; another blow and another loosened a hole in which the black inserted a short iron and began nervously grinding and prying.

Ryder, watching with oppressed and helpless fury, saw the bricks at last break and tumble faster and faster in a cloud of dust, and saw a pocket in the wall become revealed, a long, upright niche, the size, perhaps, of a man’s coffin, on end.

He tried, very suddenly, to talk.  His tongue felt thick and swollen and there seemed no words in all the world to fit his need of overcoming this fanatic madman,—­and after all, he had no chance for them, for Yussuf, with a huge palm upon his mouth, urged him suddenly backwards towards that horrible niche.

“Gently, Yussuf, gently,” said the general, suavely and with a slow distinctness that was for Ryder’s ears.  “I gave my word that I would not hurt a hair of his head—­”

Grinning, the black lifted him over the remaining wall, and set him down into the niche, leaving him standing in there like a helpless statue, tasting to the full fury of his heart the bitterness of his helplessness and the ludicrous impotence of all struggle.

“Good God, sir, you must be mad,” he said in a strained sharp voice that his ears would not have known as his own.  “Do you realize—­there will be an inquiry—­there is such a thing as law—­”

It seemed to him that he talked, in English and stammering Arabic, for a long time.  The black was kneeling, out of sight, stooping over a basin of water and his abominable sack, and Ryder was facing that silent, sardonic face, with its fantastic mustache, its evil, gloating eyes....

He stopped for very shame.  The man was mad.  Mad and drunk—­and there was no appeal from Philip drunk to Philip sober....  Mad or drunk, he had devised his vengeance shrewdly.