Instantly we all hurried forward and entered the door. Before us extended a long, straight passage, brightly illuminated by a number of electric candles. Its polished sides gleamed with blood-red reflections, and the gallery terminated, at a distance of two or three hundred feet, with an opening into a large chamber beyond, on the further side of which we could see part of a gigantic and complicated mass of machinery. Making as little noise as possible, we pushed ahead along the passage, but when we had arrived within a distance of a dozen paces from the inner end, we stopped, and Colonel Smith, getting down upon his knees, crept forward until he had reached the inner end of the passage. There he peered cautiously around the edge into the chamber, and, turning his head a moment later, beckoned us to come forward. We crept to his side, and, looking out into the vast apartment, could perceive no enemies. What had become of the sentinels supposed to stand at the inner end of the passage we could not imagine. At any rate, they were not at their posts. In the Great Power House. The chamber was an immense square room at least a hundred feet in height and 400 feet on a side, and almost filling the wall opposite to us was an intricate display of machinery, wheels, levers, rods and polished plates. This we had no doubt was one end of the great engine which opened and shut the great gates that could dam an ocean. "There is no one in sight," said Colonel Smith. "Then we must act quickly," said Mr. Edison. "Where," he said, turning to Aina, "is the handle by turning which you saw the Martian close the gates?" Aina looked about in bewilderment. The mechanism before us was so complicated that even an expert mechanician would have been excusable for finding himself unable to understand it. There were scores of knobs and handles, all glistening in the electric light, any one of which, so far as the uninstructed could tell, might have been the master key that controlled the whole complex apparatus. The Magic Lever! "Quick," said Mr. Edison, "where is it?" The girl in her confusion ran this way and that, gazing hopelessly upon the machinery, but evidently utterly unable to help us. To remain here inactive was not merely to invite destruction for ourselves, but was sure to bring certain failure upon the purpose of the expedition. All of us began instantly to look about in search of the proper handle, seizing every crank and wheel in sight and striving to turn it. "Stop that!" shouted Mr. Edison, "you may set the whole thing wrong. Don't touch anything until we have found the right lever." But to find that seemed to most of us now utterly beyond the power of man.