Astounding Stories of Super-Science, August 1930

The roof and the combat on it dropped back and beneath them like a stone as their craft ripped across the silvery dusk over the mighty frog-city. They were shooting toward the city's center, toward the green pool that was the entrance to the water-tunnel, while behind and beneath an increasing clamor of alarm spread swiftly. Norman raged futilely. "Hackett--Hackett! We can't leave him--" "Too late!" Sarja cried. "We cannot help him but only be captured again. We escape now and come back--come back--" The truth of it pierced Norman's brain even in the wild moment. Hackett had fought and held back the frog-guards only that they might escape. He shouted suddenly. "Sarja--the water-tunnel!" A half-dozen boats with frog-guards on them were rising round it in answer to the alarm! "The force-gun!" cried the green man. "Beside you--!" Norman whirled, glimpsed the long tube on its swivel beside him, trained it on the boats rising ahead as they rocketed nearer. He fumbled frantically at a catch at the gun's rear, then felt a stream of shells flicking out of it. Two of the boats ahead vanished as the shells released their annihilating force, another sagged and fell. From the remaining three invisible force-shells flicked around them, but in an instant Sarja had whirled the boat through them and down into the water-tunnel! Norman clung desperately to his seat as the boat flashed down through the waters, and then, as Sarja sent it flying out through the great tunnel's waters, glimpsed, close behind, the beams of the three Rala boats as they pursued them through the tunnel, overtaking them. Could the force-shells be fired under water? Norman did not know, but desperately he swung the force-gun back as they rushed through the waters, and pressed the catch. An instant later beams and boats behind them in the tunnel vanished.