Adult World of Violence and Death
This chapter opens above the island with an air battle between two fighter planes. ‘There was no light left’ when there was a ‘battle fought at ten miles’ height’. ‘A sign came down from the world of grown-ups’ in an ‘explosion’. It is a dead parachutist who ‘dangled’ and ‘flopped’. The twins on the mountain top had ‘both gone to sleep’. The fire has gone out.

Authority Figures
Samneric build up the fire again and chat about Ralph being “waxy’ [slang for angry] and compare him to “old Waxy at school”. They mimic “Boy-you-are-driving-me-slowly-insane.” Then they see the dead parachutist: ‘they had but one terrified mind between them’ and ‘fled’.

The Beast/Dead Parachutist

Ralph is dreaming of ‘ponies’ and ‘time for tea’ – amid ‘the sounds of nightmare’ from the other shelters.
Samneric arrive yelling: “We saw the beast.”
‘Soon the darkness was full of claws, full of the awful unknown and menace.’
Samneric say the beast has “wings”, “teeth”, “claws” and it “followed us”, “slinking behind the trees”
Jack: “This’ll be a real hunt!” He asks Ralph if he’s “frightened?”
Ralph “Course I’m frightened.” “What about the littluns?”
Jack: “Sucks to the littluns.” “We don’t need the conch any more.” [symbolises the fall of democracy in a war situation – in the face of a threat]
Ralph: “We’ve got to re-light that fire.” [the ‘beast’ is where the fire was – and they need to keep it lit, which adds to the tension of their horrible dilemma]. 

Simon ‘felt a flicker of incredulity’ ‘However Simon thought of the beast, there rose before his inward sight the picture of a human at once heroic and sick.’ ‘For a moment or two, Simon was happy to be accepted’ then walks into a tree – suggesting his other-worldly nature. His wound ‘on his forehead turned red and trickled’ suggests stigmata (wounds of Christ in crucifixion/sacrifice).
As Ralph and Jack are nervously planning to search the far side of the island, Simon says:

“I don’t believe in the beast.”

The Fort / Castle Rock 
Jack helps and is excited by the location “What a place for a fort!” Ralph says “Not me. This is a rotten place.” This prefigures the later scenes of violence: Jack saying “if an enemy came” … “one heave” … “and whee” [childish euphemism to describe killing] Ralph is more concerned that “There’s no signal now.” [no fire] He repeats “Smoke”, “Smoke”, angrily.
Roger says “We’ve got plenty of time.” The other boys are more interested in the “fort”, “wizard fort”. Ralph points out “there’s no food” there, “no shelter” and “not much fresh water”. They say, stupidly: “We can roll rocks.”
Ralph: “Are you off your rockers?”

‘Mutinously, the boys fell silent or to muttering. // Jack led the way down.’ [this is a sign of things to come]