Tarzan and the Jewels of Opar by Edgar Rice Burroughs

Achmet Zek with two of his followers had circled far to the south to intercept the flight of his deserting lieutenant, Werper. Others had spread out in various directions, so that a vast circle had been formed by them during the night, and now they were beating in toward the center.

Achmet and the two with him halted for a short rest just before noon. They squatted beneath the trees upon the southern edge of a clearing. The chief of the raiders was in ill humor. To have been outwitted by an unbeliever was bad enough; but to have, at the same time, lost the jewels upon which he had set his avaricious heart was altogether too much -- Allah must, indeed be angry with his servant.