He who had brought Tarzan appeared disgusted. "You will do well, Kalfastoban," he said, as he turned away to retrace his steps to the guard-room, "to heed the king's commands. I should hate to be wearing your harness if aught befell this speechless slave that has set every tongue in Veltopismakus going and made Elkomoelhago so jealous of Zoanthrohago that he would slip steel between his ribs were it not that he could then no longer steal the great wizard's applause." "Kalfastoban fears no king," blustered the Vental, "least of all the sorry specimen that befouls the throne of Veltopishago. He fools no one but himself. We all know that Zoanthrohago is his brain and Gefasto his sword." "However," warned the other, "be careful of Zuanthrol," and he departed. Kalfastoban Vental set the new slave to work upon the timbering of the tunnel as it was excavated from the great moraine that formed the quarry, the line of slaves coming from the surface empty handed passed down one side of the tunnel to the end, loosened each a rock, or if heavy a rock to two men, and turned back up the tunnel's opposite side, carrying their burdens back to the spiral runway used by those leaving the workings and so up and out to the new dome. The earth, a light clay, that filled the interstices between the rocks in the moraine was tamped into the opening behind the wall timbers, the tunnel being purposely made sufficiently large to permit of this. Certain slaves were detailed for this work, others carried timbers cut to the right dimensions down to the timbering crew, of which Tarzan was one. It was only necessary for this crew of three to scoop a narrow, shallow trench in which to place the foot of each wall board, set them in place and slip the ceiling board on top of them. At each end of the ceiling boards was a cleat, previously attached at the surface, which kept the wall boards from falling in after being set in place. The dirt tamped behind them fastened them solidly in their places, the whole making a quickly erected and substantial shoring. The work was light for the ape-man, though he still was weak from the effects of his wounds, and he had opportunities constantly to observe all that went on around him and to gather new information relative to the people in whose power he found himself. Kalfastoban he soon set down as a loud-mouthed braggart, from whom one need have nothing to fear during the routine of their everyday work, but who would bear watching if ever opportunity came for him to make a show of authority or physical prowess before the eyes of his superiors. The slaves about him worked steadily, but seemed not to be overtaxed, while the guards, which accompanied them constantly, in the ratio of about one warrior to every fifty slaves, gave no indications of brutality in the treatment they accorded their charges, insofar as Tarzan was able to observe.