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. [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.]
Lord of the Flies - 1 correction
Comments made in brackets are corrections from other visitors. As such, any aggressive/abusive corrections (and I get quite a few) written as if they're comments I've made myself will be ignored. To submit your own corrections for mistakes, just click the edit icon under an entry, then choose "correct entry". Some entries have "duplicated entry" after them - these are entries which were already listed on the main page, but were submitted again. I occasionally leave these online for a while, just in case they were moved in error, so don't worry about pointing them out to me.
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. [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.]



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