In chapter 12 of "Lord of the Flies", how does the author describe Ralph's flights across the island?
In Chapter Twelve, Ralph is hunted in much the same way that the pigs have been hunted, so he must flee like an animal in flight.
In the night, the outcast Ralph hears sounds coming from behind the Castle Rock, “Kill the beast! Cut his throat! Spill his blood!” Then he sees Samneric and he realizes that they are like the others, savages. They warn Ralph that he will be hunted. When Ralph asks what they are planning on doing, the boys reply, "Roger sharpened a stick at both ends." Ralph hides in the thicket.
The following morning Ralph hears Jack torturing one of the twins in order to learn his whereabouts. He sees that the boys are rolling rocks from Castle Rock in an effort to flush him out. After he is shot into the air by the landing of a large rock, Ralph sees the branches hiding him begin to shake. He thrusts his spear through the thicket and is able to wound someone.
Not long after this incident, Ralph smells smoke. He realizes that the savages are trying to burn him out. Ralph runs and is chased as though he were an animal. A spear flies over his head as the island becomes engulfed in flames.
Finally, Ralph bursts through the thicket onto the beach. When he looks up, he sees a naval officer standing over him.
Ralph must flee across the island because he is being pursued by Jack and the other boys. They want to kill him because he is the last one left from the civilized group. Ralph does not yet understand that the boys themselves were the beast on the island. His lack of understanding helped to bring down the society on the island. When he encounters the pig's skull, he still does not realize the true nature of what caused the boys on the island to devolve into savagery, but he does realize that, in order to survive, he will have to fight back. He has become the savage that he tried so hard not to become, without realiziing it. As he flees, he tries to appeal to the grain of civility left in Samneric, still unaware that savagery has won out, even though he has to think and act like an animal fleeing death. Earlier he loathed his unkempt state and now he uses that animal-like dirtiness to help him hide from the other boys. As the boys close in on Ralph, and the island is burning, he suddenly falls to the beach at the feet of the British officer who has come to the island because the smoke was sighted. Before he fell, though, his only thoughts were on basic survival at any cost.