Before he could drop it, as he circled round and round, directly over the great, flailing beams of the Air Trust search-lights, a third detonation shattered the heavens, nearly unseating him. Up sprang the roar, with wonderful intensity, reflected from the earth as from a giant sounding-board. And Gabriel noted, with keen satisfaction, that one of the huge light-beams had gone dark. "Put out _one_ of them, anyway, so far!" thought he, and swung again to westward, and once more dropped a messenger of death to tyranny. Now the bombardment became general. Trust aerial-gun projectiles began bursting all about. Every second or two, terrible concussions leaped toward the zenith; and the earth, hidden somewhere down there below the fog-blanket, seemed flaming upward like a huge volcano. One by one the search-lights, whipping the sky, went black; and now the glow of them was fast diminishing, only to be replaced by a ruddier and more intermittent glare. "The plant's burning, at last," thought Gabriel. "Heaven grant the fire may spread to the oxygen-tanks! If we can only get _those_--!" Again he launched a projectile, and again he circled over the doomed plant. A swift black shape swooped by him. He had just time to exchange a yell of warning, when it was gone. The near peril gripped his heart, but did not shake it. "Close call!" said he. If that machine and his had met, good-bye forever! But after all, the danger of collision in mid-air, or of being struck by a projectile from some other machine, above, was no greater than his comrades on the ground were facing. Not so great, perhaps. Many a one would meet his death from the aerial attack. In a war like this, a thousand perils threatened. Gabriel only hoped that Hargreaves, down below there, could hold them back, away, till the walls should have been destroyed. Circling, ever circling, now hearing some echoes of the earth-battle, some grenade-volleys and rapid-fire clattering, now deafened and all but blinded by the vast, up-belching explosions of the thanatos projectiles, Gabriel flew among the drifting mists and vapors. Still was he guided by one or two search-lights; but most of these were gone, now. Yet the glare of the conflagration, below, was luridly shuddering through the fog, painting it all a dull and awful red. Red! Suddenly words came into Gabriel's mind--the words of his own poem: ... Red as blood, red as blood! The blood of the shattered miner, Blood of the boy in the rifle pits, blood of the coughing child-slave, Blood of the mangled trainman, blood that the Carpenter shed! "For your sake! For the world's sake, this!" he cried, and hurled another thanatos. "If ever war of liberation was holy, this is that war!" Suddenly, through all the turmoil of shattering explosions, tossing air-currents and drifting, acrid smoke, he became conscious of a sudden, swift-flying pursuer.