The boy swam in an ever-widening circle, the rope unwinding from the sapling as he moved. The unwinding of the line, which he kept taut, ensured that he would cover new ground each time he rounded the pole, but without missing any. He couldn't see, because his hands stirred up mud as he traveled. Only his sense of touch told him what was on the bottom. He wasn't afraid of grabbing a crab or an eel. All underwater creatures with any mobility at all get out of the way as fast as possible. He knew the compression wave caused by his movement would warn all living creatures. His groping hands identified various pieces of wood, all natural, and assorted other objects including an old tire. There were cans, some of them food tins that had been opened, and some beverage cans, recognizable because of their triangular openings. Once he found a section of fishing pole. It was a long, tedious job. The world closed in on Rick and there was only the murk outside his mask and the rhythmic sound of his own breathing. Only his hands, constantly probing the mud, were in touch with reality. He lost all sense of time. Once, to see how much ground he had covered, he pulled himself to the pole by the line, estimating his distance. He was about fifteen feet from his starting point. He returned to the full extent of the line and started the round again, after looking at his watch. He had to hold it close to see the dial through the murk. He had been down only twenty minutes, although the time seemed much longer. Ten minutes later his hand swept over something smooth. Instantly he turned in toward the pole, and swam back around the circle for perhaps ten feet. Then, covering the ground again by crawling along the bottom, he felt for the object. His fingers touched it. His first impression was of something cylindrical, but he made no attempt to pick it up. He needed to explore it thoroughly, first. His breathing was faster, and he knew his pulse had accelerated at the moment of discovery. If this continued, he would use air too fast. He willed himself to slow his breathing, and for a few seconds he stopped altogether. In that instant, Rick heard a slap on the water, then another. He waited, holding his breath. There was a pause, then more gentle slaps. He counted them. One, two, three, four--the signal for danger!