In Chapter One of Lord of the Flies, the boys originally gravitate toward the beach because Ralph uses the conch to make a loud trumpeting sound. Piggy actually comes up with the idea to use the conch as a signal:
"We can use this to call the others. Have a meeting. They'll come when they hear us--" (16).
Even though Ralph remains skeptical of Piggy's notion, he eventually succeeds in blowing the conch, which resulted in a "deep harsh note [that] boomed under the palms" (17). Shortly after the first notes sounded, many of the boys emerge from the palms and jungle, including Jack Merridew and his choir. Many of the boys mistook the conch for a trumpet, falsely hoping that some sort of rescue mission or ship had come to save them.