They collect dead wood and use lenses from Piggy's glasses to focus the sunlight and set wood on fire.
(Since Piggy had been - very likely - nearsighted, his glasses would be useless. Nearsighted people need diverging lenses which cannot set fire. It seems to be a serious hole in the plot, for nitpickers.)
The boys start the fire in "Lord of the Flies" by using Piggy's glasses to focus the sun's rays and ignite dry leaves and twigs. Initially, they struggle to keep the fire going and maintain it as a signal for passing boats or planes.
They use Piggy's specs/glasses to start the fire.
penis
The boy who was talking about the "beastie"
Piggy finds the spectacles in Lord of the Flies. He uses them to start the signal fire and later relies on them to see clearly.
Piggy is the one who suggests using the glasses to start a fire in "Lord of the Flies." He realizes that the lenses can concentrate sunlight to create a flame.
In chapter 2 of Lord of the Flies, the boys start the fire by using Piggy's glasses to focus the sun's rays onto dry leaves and twigs. This method allows them to create a flame and start the fire for a signal to potential rescuers.
The boys use Piggy's glasses to start a fire in the book, "Lord of the Flies." Ralph moved the glasses around until an image of the sun shined on the rotten wood, and smoke began to swirl up.
They cut wood and then used Piggy's glasses to reflect the sun so the wood would catch fire.
Ralph thinks that the beast on top of the mountain top is preventing them from the fire
the glasses symbolize hope because with the glasses the boys can start a signal fire,cook,and have heat
Part of the island burns and the boy with the birthmark on his face dissapears
Jack and his tribe of hunters were responsible for moving the fire in "Lord of the Flies" as they prioritized hunting and their own desires over maintaining the signal fire for rescue.
The side of the island with the little bit of smoke in "Lord of the Flies" is the south side of the mountain. This is where the boys start a signal fire in an attempt to attract passing ships for rescue.