10 accidental discoveries that changed the world

From penicillin and anaesthesia to saccharin and silly putty, chance played a major role in some of the world’s great inventions.
1. Penicillin

Inventor: Alexander Fleming
Year: 1928
What Happened: Halfway through an experiment with bacteria, Alexander Fleming up and went on holidays. Slob that he was, he left a dirty petri dish in the lab sink.
Big Discovery: When he got back, he found bacteria had grown all over the plate, except in an area where mold had formed.
As a Result: That discovery led to two things: 1) penicillin and 2) Mrs. Fleming hiring a maid.
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2. Anaesthesia

Inventor: Horace Wells
Year: 1844
What Happened: In its salad days, nitrous oxide was strictly a party toy, since it made people howl like hyenas. But a friend of the dentist took too much of the stuff at a laughing-gas stage show and gashed his leg.
Big Discovery: The friend hadn’t realised he’d hurt himself.
As a Result: Nitrous oxide became an early form of anaesthesia.
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