Asked by: Edward Seymour, Hove
Found in 1938 by a German archaeologist, the ‘Baghdad Battery’ could be 2,000 years old, and consists of a clay jar, a copper cylinder and an iron rod. If filled with a weak acid, like vinegar, the combination produces around 1 volt.
Yet while even some experts refer to it as a battery, its true origin and purpose remains unclear. One idea is that it was used for electroplating objects with precious metals.
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Authors
Robert is a science writer and visiting professor of science at Aston University. He likes maths, West End musicals and hamsters.
