Everything worked out practically as Brandon had foretold, and a few days later, their acceleration somewhat less than terrestrial gravity, he called another meeting in the control room. He came in grinning from ear to ear, accompanied by the two Martians, and seated himself at his complex power panel. "Now watch the professor closely, gentlemen," he invited. "He is going to cut that beam." "But you can't," protested Pyraz Amonar. "I know you can't, ordinarily, when a beam is tight and solid. But that beam's as loose as ashes right now. I told you I had a hunch, and Alcantro and Fedanzo worked out the right answer for me. If I can cut it, Quince, and if their screens go down for a minute, shoot your visiray into them and see what you can see." "All x. How much power are you going to draw?" "Plenty--it figures a little better than four hundred thousand kilofranks. I'll draw it all from the accumulators, so as not to disturb you fellows on the cosmic intake. We don't care if we do run the batteries down some, but I don't want to hold that load on the bus-bars very long. However, if my hunch is right, I won't be on that beam five minutes before it's cut from Jupiter--and I'll bet you four dollars that you won't see the original crew in that fort when you get into it." He set upper and lower bands of dirigible projectors to apply a powerful sidewise thrust, and the _Sirius_ darted off her course. Flashing a minute pencil behind the huge heptagon, Brandon manipulated his tuning circuits until a brilliant spot in space showed him that he was approaching resonance with the heptagon's power beam. Micrometer dials were then engaged and the delicate tuning continued until the meters gave evidence that the two beams were precisely synchronized and exactly opposite in phase. Four plunger switches closed, that tiny pilot ray became an enormous rod of force, and as those two gigantic beams met in exact opposition and neutralized each other, a solid wall of blinding brilliance appeared in the empty ether behind the Vorkulian fortress. As that dazzling wall sprang into being, the sparkling green protection died from the walls of the heptagon. "Go to it, Quince!" Brandon yelled, but the suggestion was entirely superfluous. Even before the wall-screen had died, Westfall's beam was trying to get through it, and when the visiray revealed the interior of the heptagon, the quiet and methodical physicist was shaken from his habitual calm. "Why, they aren't the winged monsters at all--they're _hexans_!" he exclaimed.