As an allegory, The Lord of the Flies, employs fire is a symbol of power, just as it represents power in the myth of Promethesus, who stole fire from the gods and gave it to man.
- As a signal to the outside world of civilization, fire represents the power of rescue and return to civilization.
- The fire also represents the reponsibility that civilization demands as Ralph insists that the boys keep the fire going so that they can be rescued. Their failure to do so results in their being missed by a passing ship. In Chapter Five Ralph tells the boys, that the fire is the most important thing...."smoke is more important than the pig."
- When Jack and the hunters steal the fire, as Prometheus does in the ancient myth, the evil and destructive power of anarchy is symbolized as Jack and the sadistic Roger gain control of the boys
- The resulting regression to savagery is symbolized by the fire that sweeps the island, "burning" away the vestiges of society and threatening death to Ralph:
Acres of black and yellow rolled steadily toward the sea....like flames, as though they were a kind of wild life, crept as a jaguar creeps on its belly toward a line of birch...Beneath the capering boys a quarter of a mile square of forest was savage with smoke and flames. (Chapter Two)
To me, fire symbolizes a couple of different things. It can be a link to civilization -- a sign that the boys are still civilized and want to be rescued. However, it can also be a symbol of how destructive savagery can be.
The signal fire is a link to civilization. It is one of the first things that the boys try to do when they are still interested in being rescued. As they get less interested (and less connected to civilization) they tend to let the fire go out.
The wildfires are destructive. They kill accidentally (the boy with the birthmark) and they are used in an attempt to kill intentionally (trying to get Ralph out where they can kill him).