A new reverberating quality came into the echoes from the shore. The pilings of the wharf were nearby, now. They multiplied the sounds they returned. The _Esperance_ loomed up. Terry cut off the motor, the little boat drifted to contact, and Deirdre scrambled to the yacht's deck, and then took the bow line and fastened it. This was absurdly commonplace. It was exactly what would have been done on the return from any usual ride. "Go tell the others what we found," said Terry. "I'm going to see if there's more than one of those things around." "Not ..." "No," he assured her. "I'm only going to use the fish-driving horn." Deirdre looked at him in distress. "Be careful! Please!" She kissed him suddenly, scrambled to the wharf, and set off at a run toward the shore. Terry stared hungrily after her. They'd come to a highly personal decision the night before on the _Esperance_, but it still seemed unbelievable to him that Deirdre felt about him the way he felt about her. He went forward to set up the fish-driving combination. One part of him thought vividly of Deirdre. The other faced the consequences that might follow if the bolides were not bolides, and if the plastic gadgets and the nasty-sounding underwater hums were products of an intelligence which could make bolides change their velocity in space; which made them fall in the Luzon Deep in the China Sea and nowhere else. He set up the recorder with its loop of fish-driving hum. He put the horn overboard, carefully oriented to spread its sound through all the enclosed shallow water of the lagoon. He turned the extra amplifier to maximum output, to increase the effectiveness of the noise, and turned on the apparatus. The glassy look of the lagoon-water vanished immediately. Fish leaped crazily everywhere, from half-inch midgets to lean-flanked predators a yard and more in length. There was no square foot in all the shallows where a creature didn't struggle to escape the sensation of pins and needles all over its body. And these pins and needles pricked deep. Flying-fish soared crazily, and they were the most fortunate because so long as they flew, the tormenting water-sound did not reach them. But many of them landed on the beach, and even among the palms. In the spot where blind and snakelike arms had tried to destroy Terry and Deirdre, the lashing and swirling was of a different kind. Something there used enormous strength to offer battle to a noise. The water was whipped to froth. Twice Terry saw those rope-like arms rise above the water and flail it. This particular sort of tumult, however, appeared only in one spot. So there was only one such creature in the lagoon. When Davis and the others came down from the tracking station, Terry turned off the horn. He was applying soothing ointment to the raw flesh of his leg.