In the first part of Chapter Four of Lord of the Flies, there is foreshadowing of the boys increasing release of the vestiges of civilization. Although they followed the "northern European tradition of work, play, and food throughout the day, the "littluns" cried for their mothers less than before, and they played among themselves, ignoring the older boys as they play in the sand.
Roger and Maurice, who emerge from the forest, kick sand into the eyes of three littluns.
Now, though there was no parent to let fall a heavy hand, Maurice still felt the unease of wrongdoing.
Later, Roger hides behind the palm trees and he picks up a stone, aims, and hurls it at little Henry, but threw it with the intention of missing.
The stone, that token of preposterous time, bounced five yards to Henry's right and fell in the water....Here was the taboo of the old life.
Further, Jack tells Roger that he is making a mask to "try to look like something else" in order to throw the pigs off. When Jack finishes with his mask, he peers into the water at himself. Now, he is astonished as he is "an awesome stranger." As Bill sees it, he begins to laugh, but suddenly "he fell silent and blundered away through the bushes" recognizing the savage appearance of the mask. With the painted mask on his face, Jack can hide his civilized face and is, therefore, freed some any shame or self-consciousness. And, yet, "[T]he mask compelled them" forward into the forest.
*The mask, then, is symbolic of the entrance into savagery. the throwing off of all the vestiges of society, even those final ones which prohibit Roger from striking Henry with the stone and that which makes Maurice feel somewhat guilty about kicking sand into the faces of the littluns. The mask creates a new face, a new facade behind which Jack and the hunters can release savage urges and taboos.