What page does Piggy break his glasses?

Keeping this in view, what happens to Piggy's glasses in Chapter 11?

Jack commands Ralph to leave his camp, and Ralph demands that Jack return Piggy's glasses. But the boulder strikes Piggy, shatters the conch shell he is holding, and knocks him off the mountainside to his death on the rocks below.

One may also ask, what happens to Piggy's glasses in Chapter 4? Piggy's broken lens: Towards the end of Chapter 4, Jack slaps Piggy in the face and breaks one of the lenses of his glasses. Piggy's glasses symbolically represent reason, scientific thought, and the ability to think logically.

In respect to this, what does Piggy's broken glasses symbolize?

Piggy's glasses symbolize civilization and when they are broken it symbolizes the destruction of the civilization the boys had at the begining of the book. The conch represents 'Democracy and free speech' or order between the boys and how they could not speak out of turn if they didn't have the conch.

What happens to Piggy's glasses in Chapter 10?

That night, Jack and his hunters attack while everyone is asleep. Ralph and Eric beat each other up, and Piggy protects the conch, while Jack steals Piggy's glasses. The "civilized" boys stop trying to keep the signal fire burning at night: a symbolic surrender to savagery.