What is the language difference between Piggy and Simon's death?

Simon's death was the result of mistaken identity by a group of over excited boys during an evening thunderstorm. The description of Simon's death conveys the almost animal ferocity of the attack by the boys. The build up to his death stresses the opressive nature of the storm, the lightning flashes and the rhymically, hypnotic quality of the pig dance, which the boys were performing. Piggy's death in constrast was the direct consequence of the action of one boy who, in full daylight and aware of the possible consequences, just went ahead and launched a boulder from the top of castle rock simply because he wanted to.The build up mentions Roger throwing pebbles and small stones in Piggy's direction and his desire to cause hurt and pain coupled with the means at his disposal and Piggy's chastising simply led to an inevitable conclusing. Roger simply relieved his pent up desires and irritaion with Piggy by squashing him like a troublesome insect. The entire episode was like a boulder rolling down a cliff and the description built up momentum until it reached its climax.