Lord of the Flies

1 corrected entry

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Corrected entry: As Piggy is short-sighted, his spectacles could not be used as a "magnifying glass" to light a bonfire: lenses for short-sightedness would scatter, not concentrate, the sun's rays.

Correction: Not quite correct. It is possible to light a fire using glasses, as long as the lenses have one concave and one convex surface. Focusing the light through the convex lens, and coming out the concave side will allow a point of light to focus on tinder and ignite it. The stronger the prescription, the better. If it is possible to light a fire focusing sunlight through an icicle (which has been tested and shown to work), it is definitely possible, and easier, to ignite tinder using glasses, near- or farsighted. It's not whether the person is near- or farsighted, but the shape of the lens that allows the focusing of light onto tinder.