But now we were within the last dozen levels of the plaza's surface, and were down with all the eagerness of renewed hope. For in the plaza there beneath us there lay still the unguarded cruisers, their officers and crews gathered in the great tower down which we were creeping. Another level--another--and down we swung through the dusk, in such a descent as surely man never had made before. The plaza was close beneath, the window of our cell now far above. From far around that plaza, from Berlin and from all the air-cities about, we heard the great hum of final preparations being made. I knew they were ready now to sally forth upon their gigantic attack. But we were within the last few levels of the plaza, now, swinging down with mad haste from window to window toward its smooth surface. And then it was, when we were within a few yards of that surface, that I heard a dim cry from far above. "Down now with all your strength, Hilliard!" I cried to my friend above me. "They've come to our cell after us--are giving the alarm!" "The nearest cruiser there below!" he exclaimed thickly as he swung madly down after me. "We'll make it yet!" But now the cry of our guards high above was being taken up and repeated by other voices in the great electrostatic tower. That cry was coming down through it from level to level, even as we swung from the last window to the level plaza. And, as we staggered across it, toward the open door of the nearest cruiser, there came a series of popping detonations from above and the next moment little flares of terrific heat were bursting all about us as the guards shot their heat cartridges down toward us! From their great height and through the dusk their aim was poor, and in a moment more we were at the cruiser's open door. But now the alarm was spreading over all the tower behind us, and at the same moment that we flung ourselves in through the cruiser's open door, slamming it behind us, we heard a wild clamor of voices from the power-tower's base! The next instant, though, we were bursting up into the cruiser's bridge-room and for a moment of agony I fumbled at its controls, set differently from those of our American cruisers. Then the motor-stud had clicked beneath my fingers and, as the great electric motors beneath droned suddenly loud with the current rushing through them, I sent all their power into the cruiser's tube-propellers. Up it went rushing, up and away at terrific speed and at a steep slant, even as a mass of green-uniformed figures burst from the electrostatic tower into the plaza! Out and over that plaza at terrific speed we shot, out and upward at such awful mounting velocity that, before the great batteries of heat-guns around us could turn, before the alarm from the power-tower had time to spread, we were whirling up and through the dusk over all the massed towers and gleaming lights of the great air-city Berlin!