Berla of Zollaria. It lay there, huge, dark, slumbrous, safe; secure as the night pall wrapped it in all, seeming, undisturbed by any alarm of danger--unapproached by any force of foes. For what could harm Helmor's city, behind its darkly outlined walls? Four hundred miles of mountain, plain, and desert lay between it and the Tamarizian border--and as yet, save for the sending of a delegation to parley, Tamarizia had not moved. Dark, silent, it lay, save for where on either side of one of its many gates, the fire urns flared. And yet on the darkened terrain beyond them crouched the squat, wide-winged shape of the Tamarizian plane, with its two men, watching, watching. And somewhere--high above it rode the blimps, of which there was no sign. Yet they were there, and the plane was squatted, watching--and they were things that, swifter than any method known to Zollaria's craft--swifter than the swiftest racing gnuppas--could cross mountain and desert and plain. Then suddenly--without sound, so high they rode--from out of the blue-black void of the heavens--there showed a winking light. Ruddy it was as a falling star--as it glowed briefly and vanished like a fading spark. And yet, seeing it, one knew that under cover of the darkness, before the moons of Palos wheeling up like racers of the night revealed them, the blimps were stealing in. Once more the ruddy pin-point winked, twice, thrice, and vanished, and as it faded for the last time it was answered by Croft himself from the plane. Briefly his torch glowed and was extinguished and the spot in the heavens did not appear again. Only Jason spoke to the flier. "Be ready, Avron." And the man replied, "Aye, lord," climbed into the pit of the fuselage, and began strapping himself in place. Croft followed suit. The two men sat staring out towards the walls of Berla, where the fire urns still made flickering flares against the gates. And that was all. Save for their breathing, the whisper of the night wind round them, there was no sound. Silent as death itself was the blimps' approach, and as unsuspected, until presently an arc of silver appeared above the eastern horizon, and up shot the first of the twin Palosian moons. Its upflung rays fell on a wondrous sight. They struck against the giant dirigibles, turning them into slowly drifting things of silver--huge, unbelievable, weird as the moonlight struck upon them, like monstrous dream shapes--unthinkable bubbles wafted forward on some unsensed breeze. So they must have burst upon the startled sight of Berla's people, first, soaring high above the city, circling as though in search of some definite spot, before they paused, appeared to hover for an instant, and began settling down. "Zitu!" Avron whispered tensely under his breath. "Aye," said Zitu's Mouthpiece as though in answer. "Watch ye now, Avron--watch."