The green waters rose about them in the lock and they swung off. Adam's voice came clearly through the earphones of the party. "Be careful everyone! This is a regular jungle of those chain-weeds." Paulette's voice answered. "Look, Adam! Where I'm pointing. There's something different over there, little round things, dark red, with a few yellow ones." "I see them, Paulette. I don't think.... Jake, I don't like this. Let's test that bottom and get back as soon as we can." The men stooped and scraped in the silt with their metal tools, reporting results. "Not over six inches to rock here." "Eight inches here." "Just about as shallow here as before." "Take a few samples, then. Make it as quick as you can. As soon as you get your samples move back, be ready to ascend to the main lock." * * * * * Adam could see nothing but the cloudy liquid around him, stirred to green milk as the sampling of the silt raised a murk around him. "Paulette," he called, "what's your compass reading?" "Nineteen-O-thirty south. Sixty-three--seven, west." "I can't see you. Move due east two long steps and stand still. I'll reach for you." She complied and called out to him. "What's your reading now?" he asked, and she thought his voice sounded strange as she replied, "Same south reading. Sixty-three--six, west." "Jake! Where are you and what's your reading?" "I'm right here, Mr. Adam. Can't see you? This silt doesn't seem to settle down. There's a current of some kind carrying it; I can just stand against it. My reading's eighteen-forty--forty-two south; sixty-two--fifteen west." "Bjornsen, Rossiter! Report and extend hands. If you don't touch anyone, reach out with the safe ends of your bomb-spears and swing them in a circle till you do.... Ah, who's that who just touched me?" "Rossiter, sir." "That makes three of--" The words were suddenly cut off by the shock of an explosion that nearly tore them from their feet and a heavier cloud of the milky silt came eddying past, fragments of chain-weed moving through it. Burchall's voice came through the earphones. "Attacked! New kind of animal! Eighteen-forty--twenty-one south. Twenty--thirty-two west!" "Never mind the bearings!" cried Adam. "Rossiter, Paulette! Hang on to the ends of these spears, and take three steps with me, don't lose contact!" The three leaped as one, then again and again, through the murk in which everything was invisible. As they touched bottom at the end of the last leap, Adam saw a long writhing arm, with a barbed tip at the end of it, swing past his helmet view-ports, caught a gasp from Jake through his earphones, and then felt Paulette at his side pull free from his gripping hand and reach up with the bomb-spear. There was the shock of another explosion. Down he went, and saw something murky with whirling arms fly past the view-ports. Then Paulette's voice came through, clear and triumphant.