英語(yǔ)時(shí)差:別在家里試?。?！

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Time once again for Don't Try This At Home, the segment of our show in which we discourage people from doing things that may destroy your house or frighten the neighbors. A healthy sense of curiosity is essential to the scientific spirit, but safety must come first! Let's see what's in the file . . .  (RUSTLING PAPERS) . . . building your own parachute . . . no . . . My Pet Python . . . no . . .

Aha! "Did Ben Franklin really discover electricity with a kite?" That's a good one. Everybody has heard the famous story of how pioneering experimenter--and part-time founding father--Ben Franklin tied a key around a kite string and flew the kite in a thunderstorm. The kite was hit by lightning, and zap! Franklin had discovered electricity.

Well, it makes a better story than it does an experiment. The danger is that lightning is not something you want to play with, and you certainly don't want to attract it to yourself! Were this story to be true, I'm afraid, the result would have been fried Franklin.

What Ben actually did in his famous 1752 experiment was to cause some excess electrical charge near a storm cloud to ground out through his kite string--still an impressive demonstration, but a much less powerful prospect than an actual lightning strike.

Nor is it true that Franklin discovered electricity, as people tend to say. What he was trying to do was to demonstrate that lightning itself is simply a powerful electric discharge between the clouds and the earth. In this he was entirely correct.