"Jack smacked Piggy's head. Piggy's glasses flew off and tinkled on the rocks. Piggy cried out in terror:
He went crouching and feeling over the rocks but Simon, who got there first, found them for him. Passions beat about Simon on the mountain-top with awful wings.
'One side's broken.'
Piggy grabbed and put on the glasses. He looked malevolently at Jack."
Which word(s) or phrase(s) from the passage above best illustrate(s) the symbolic change in the boys that occurs around the time the ship passes by the island?