* * * * * Stuart went slowly after the others. They had crossed the threshold now, and were pacing along a tunnel, lit with cold blue brilliance, that curved very gradually toward the left. Behind him a panel closed. The cloak swayed like a great bloodstain behind him, moving in a motion not entirely caused by Stuart's movements. He tried again to unfasten it, but the clasp at his throat only drew tighter. And the tingling sensation increased along his spine. An artificial synapse ... blocking his nerve-ends so that he could not draw upon the Protectors' power.... At his left was an alcove in the tunnel wall. It was filled with coagulated light ... bright with glaring flames ... flame-hot. Within that white curtain stirred swift movement, like the leaping of fires. Above the recess a symbol was embossed in the stone. The sign of Mercury. "Mercury," said the voice in Stuart's mind. "The Servant of the Sun. The Swift Messenger. Mercury, that drinks the Sun's fires and blazes like a star in the sky's abyss. First in the Long Orbit--Mercury." The crowd of prisoners, dull-eyed, swayed to and fro, a ripple of excitement rustling through them. Abruptly the Martian girl darted forward-- Was engulfed in the milky flames. Stood there, while curdled opalescence veiled her. On her face sheer horror, as-- "The Aesir feed," the voice whispered. "They drink the cup of her life ... to its last dregs." The captives were moving again. Silently Stuart followed them along the tunnel. Now another recess showed in the wall. Blue ... blue, this time, as hazy seas of enchantment ... misted with fog, with slow shifting movement within it.... "The sign of Venus," said the voice. "The Clouded World. Planet of life and womb of creation. Ruler of mists and seas--Venus!" The Earthman was drawn into the alcove. Stood there, while azure seas washed higher and higher about him. Through that glassy veil his face glared, stiff with alien fear.... The sacrifices went on. There was no alcove, no symbol for Earth. The Aesir had forgotten the world that had been their place of birth. "Mars! Red star of madness! Ruler of man's passion, lord of the bloody seas! Where scarlet sands run through Time's hourglass--Mars, third in the Long Orbit!" The crimson glow of a dusty ruby ... the face of a Venusian, strained, twisted in agony ... the hunger of the Aesir.... "The Little Worlds! The Great Belt that girdles the Inner System! The Broken Planet--" Tiny goblin lights, dancing and flickering, blue and sapphire and dull orange, wine-red and dawn-yellow-- The hunger of the Aesir. "Jupiter! Titan! Colossus of the Spaceroads! Jupiter, whose mighty hands seize the ships of man and drag them to his boiling heart! The Great One-fifth in the Long Orbit!" The hunger of the Aesir. "Ringed Saturn light-crowned! Guardian of the outer skies! Saturn--" Uranus ... Neptune.... Pluto. The hunger of the Aesir....