terrors for me, and it met cold steel instead of the tender flesh its cruel jaws gaped so widely to engulf. An instant later I drew my blade from the still heart of this great Barsoomian lion, and turning toward Tars Tarkas was surprised to see him facing a similar monster. No sooner had he dispatched his than I, turning, as though drawn by the instinct of my guardian subconscious mind, beheld another of the savage denizens of the Martian wilds leaping across the chamber toward me. From then on for the better part of an hour one hideous creature after another was launched upon us, springing apparently from the empty air about us. Tars Tarkas was satisfied; here was something tangible that he could cut and slash with his great blade, while I, for my part, may say that the diversion was a marked improvement over the uncanny voices from unseen lips. That there was nothing supernatural about our new foes was well evidenced by their howls of rage and pain as they felt the sharp steel at their vitals, and the very real blood which flowed from their severed arteries as they died the real death. I noticed during the period of this new persecution that the beasts appeared only when our backs were turned; we never saw one really materialize from thin air, nor did I for an instant sufficiently lose my excellent reasoning faculties to be once deluded into the belief that the beasts came into the room other than through some concealed and well-contrived doorway. Among the ornaments of Tars Tarkas’ leather harness, which is the only manner of clothing worn by Martians other than silk capes and robes of silk and fur for protection from the cold after dark, was a small mirror, about the bigness of a lady’s hand glass, which hung midway between his shoulders and his waist against his broad back. Once as he stood looking down at a newly fallen antagonist my eyes happened to fall upon this mirror and in its shiny surface I saw pictured a sight that caused me to whisper: “Move not, Tars Tarkas! Move not a muscle!” He did not ask why, but stood like a graven image while my eyes watched the strange thing that meant so much to us. What I saw was the quick movement of a section of the wall behind me. It was turning upon pivots, and