“You’ll see what I’ve been doing,” he replied truculently, “and it’s done—it’s done—it can’t ever be undone. I’ve seen to that.” I grabbed him roughly by the shoulder. “What do you mean? Tell me what you have done, or by God I will kill you with my own hands,” for I knew, not only from his words but from his expression, that he had accomplished something which he considered very terrible. The man was a coward and he quailed under my grasp. “You wouldn’t dare to kill me,” he cried, “and it don’t make any difference, for we’ll all be dead in a few hours. Go and look at your damned compass.” CHAPTER II THE HEART OF THE MOON Norton, whose watch it was, had already hurried toward the pilot room where were located the controls and the various instruments. This room, which was just forward of the engine-room, was in effect a circular conning-tower which projected about twelve inches above the upper hull. The entire circumference of this twelve inch superstructure was set with small ports of thick crystal glass. As I turned to follow Norton I spoke to West. “Mr. West,” I said, “you and Mr. Jay will place Lieutenant Commander Orthis in irons immediately. If he resists, kill him.” As I hurried after Norton I heard a volley of oaths from Orthis and a burst of almost maniacal laughter. When I reached the pilot house I found Norton working very quietly with the controls. There was nothing hysterical in his movements, but his face was absolutely ashen. “What is wrong, Mr. Norton?” I asked. But as I looked at the compass simultaneously I read my answer there before he spoke. We were moving at right angles to our proper course. “We are falling toward the Moon, sir,” he said, “and she does not respond to her control.” “Shut down the engines,” I ordered, “they are only accelerating our fall.” “Aye, aye, sir,” he replied. “The Lunar Eighth Ray tank is of sufficient capacity to keep us off the Moon,” I said. “If it has not been tampered with, we should be in no danger of falling to the Moon’s surface.” “If it has not been tampered with, sir; yes, sir, that is what I have been thinking.” “But the gauge here shows it full to capacity,” I reminded him. “I know, sir,” he replied, “but if it were full to capacity, we should not be falling so rapidly.” Immediately I fell to examining the gauge, almost at once discovering that it had been tampered with and the needle set permanently to indicate a maximum supply. I turned to my companion. “Mr. Norton,” I said, “please go forward and investigate the Lunar Eighth Ray tank, and report back to me immediately.” The young man saluted and departed. As he approached the tank it was necessary for him to crawl through a very restricted place beneath the deck. In about five minutes Norton returned. He was not so pale as he had been, but he looked very haggard. “Well?” I inquired as he halted before me.