The air service boys rejoiced that the victory was won.
The roar of guns from below had ceased, and as the Yankees above could not find any enemy plane against which to pit their strength, they, too, no longer scurried this way and that, each one like an avenging Nemesis.
Looking down Jack was appalled at what he saw. It seemed almost as though the end of the world had come. Huge volumes of acrid smoke slowly swept along on the night air, with here and there a lurid tongue of angry flame, looking like a serpent's tongue, stabbing the gloomy curtain.
He had seen vivid pictures in colors of an eruption of Vesuvius, and to his mind this presented just such an appalling spectacle. There could never be any doubt regarding the awful power of those latest of Yankee bombs. The German stronghold that an hour before had stood in arrogant pride, meant to be a stumbling block in the path of Pershing's victorious army, had been so shattered that it would hardly be noticed in the general advance of the oncoming host of boys in khaki.
But there was the signal to gather once more in formation of twos for the homeward journey. There would always be a chance that the furious Huns might gather a fresh force of aerial fight-
