bulbs, the universal lighting medium of Barsoom. These same lamps may have been doing continuous duty in these subterranean chambers for ages, since they require no attention and are so compounded that they give off but the minutest of their substance in the generation of years of luminosity. We had proceeded for but a short distance when we commenced to pass the mouths of diverging corridors, but not once did Woola hesitate. It was at the opening to one of these corridors upon my right that I presently heard a sound that spoke more plainly to John Carter, fighting man, than could the words of my mother tongue—it was the clank of metal—the metal of a warrior’s harness—and it came from a little distance up the corridor upon my right. Woola heard it, too, and like a flash he had wheeled and stood facing the threatened danger, his mane all abristle and all his rows of glistening fangs bared by snarling, backdrawn lips. With a gesture I silenced him, and together we drew aside into another corridor a few paces farther on. Here we waited; nor did we have long to wait, for presently we saw the shadows of two men fall upon the floor of the main corridor athwart the doorway of our hiding place. Very cautiously they were moving now—the accidental clank that had alarmed me was not repeated. Presently they came opposite our station; nor was I surprised to see that the two were Lakor and his companion of the guardroom. They walked very softly, and in the right hand of each gleamed a keen long-sword. They halted quite close to the entrance of our retreat, whispering to each other. “Can it be that we have distanced them already?” said Lakor. “Either that or the beast has led the man upon a wrong trail,” replied the other, “for the way which we took is by far the shorter to this point—for him who knows it. John Carter would have found it a short road to death had he taken it as you suggested to him.” “Yes,” said Lakor, “no amount of fighting ability would have saved him from the pivoted flagstone. He surely would have stepped upon it, and by now, if the pit beneath it has a bottom, which Thurid denies, he should have been rapidly approaching it. Curses on that calot of his that warned him toward the safer avenue!” “There be other dangers ahead of him, though,” spoke Lakor’s fellow, “which he may not so easily escape—should he succeed in escaping our two good swords. Consider, for example, what chance he will have, coming unexpectedly into the chamber of—”