Urging the professor and Taggert into the _Sphere_ hurriedly, Robert slipped the automatic out of his pocket, thanking his lucky stars that he had brought it with him. Without hesitation he blazed away over the heads of their pursuers as they rushed forward, hoping to halt them for an instant. But they seemed undaunted. On they came in great bounds, shouting excitedly. Having done what he could to keep them away from the _Sphere_, Robert hurried into the passage just as the leader came up. As the latter darted after him Robert fired. The Martian went down, but the others pressed forward, brandishing saberlike weapons. Unable to lift the trap-door into place because of the body of the wounded Martian upon it, Robert was about to shout to Taggert to raise the _Sphere_, when one of the Martians leaped over his prostrate fellowman and struck at Robert with his weapon. By an unlucky bit of chance the blade struck the automatic from Robert’s hand even as he fired again. He could hear the gyrostats humming and had just presence of mind enough to yell to Taggert to raise the _Sphere_ when there came a roar and a flash by his ear and the vicious Martian’s weapon clattered on to the steps as he staggered back, blocking for a moment the others behind him. The rays from the small globe in the ceiling now lighted the passage. “Close shave, Robert,” came Professor Palmer’s voice, and once more the roar of his firearm deafened them in the narrow passage. The Martians’ rush was checked for a moment, and in that instant they had lost. The _Sphere_ trembled. As a great shout of baffled rage welled up from without, Robert knew that they finally were off. Stung by their failure, two Martians rushed at the manhole. One of them managed to grip the rungs outside. The next instant he was precipitated forcibly back to the ground as the _Sphere_ shot upward, wrenching the rungs from his grasp. But Robert’s earlier assailant still sprawled, wounded and partly dazed, upon the lower steps. Then, abruptly, before they could prevent it, he rolled off into space with a wild cry! Slamming the manhole cover shut, Robert and the professor made their way up into the main chamber. The princess was waiting for Robert with great anxiety. There, for the first, time, Robert met Hakon, her father, a dignified and robust man of middle age, with an imperious though pleasant manner. The beard, as affected by the emperor, was absent, but he wore a short, gray mustache that matched his heavy, graying hair. “I can not express my gratitude for the service you and your companions are doing for my daughter and me, my friend,” he said in a pleasing, resonant voice. “I can only say that you shall all be fittingly rewarded upon our arrival in my country.” “The privilege of rescuing your Highness and the princess is sufficient reward,” replied Robert. “Can’t we go back and lick their army for you or something?” asked Taggert, looking at the princess in vast admiration.