"My God!" whispered Stanley. "There are thousands of them!" * * * * * There were. And that they were in distress was evident. The layers on the floor were weaving and shifting constantly as the bottom creatures struggled feebly to rise to the top of the mass and be relieved of the weight of their brothers. Also they were famished.... One of the blood red, gigantic worms floated near the cave entrance. Like lightning the nearest Quabos darted after it. In a moment the prey was torn to bits by the ravenous monsters. The other side of the story was immediately portrayed to us. With the emerging of the reckless Quabos, a sea-serpent appeared from above and snapped up three of their number. Evidently the huge serpent considered them succulent tidbits, and made it its business to wait near the cave and avail itself of just such rash chance-taking as this. While we watched the nightmare scene, a Quabo disengaged itself from the parent mass and floated upward into the clear, giving us a chance to see more distinctly what the creatures looked like. There was a black, shiny head as large as a sugar barrel. In this were eyes the size of dinner plates, and gleaming with a cold, hellish intelligence. Four long, twining tentacles were attached directly to the head. Dotted along these were rudimentary sucker discs, that had evidently become atrophied by the soft living of thousands of the creature's ancestors. As though emerging from the pool into which we were gazing, the monster darted viciously at us. At once it disappeared: the fish-servant through whose eyes we were seeing all this had evidently retreated from the approach; although, protected by its spines, it could not have been in actual danger. "How dost thou know of the tunneling?" I asked Aga. "Thy fish-men cannot be present there, in the rear of the tunnel, to report." "My artisans have knowledge of each forward move," she answered. "I will show thee." * * * * * We walked back to the palace and descended to a smooth-lined vault. There we saw a great stone shaft sunk down into the rock of the floor. On this was a delicate vibration recording instrument of some sort, with a needle that quivered rhythmically over several degrees of an arc. "This tells of each move of the Quabos," said Aga. "It also tells us where they will break through the city wall. How near to us are they, Kilor?" she asked an attendant who was studying the dial, and who had bowed respectfully to Aga and myself as we approached. "They will break into the city in four rixas at the present rate of advance, Your Majesty." Four rixas! In a little over sixteen days, as we count time, the city of Zyobor would be delivered into the hands--or, rather, tentacles--of the slimy, starving demons that huddled in the cavern outside! Somberly we followed Aga back to her apartment. * * * * *