The Oxford Electric Bell Has Been Ringing for 180 Years

The Oxford Electric Bell, also known as the Clarendon Dry Pile, is an experimental electric bell set up in 1840 at the University of Oxford. It has been ringing almost continuously ever since, powered by two dry piles that have lasted over 180 years. The bell operates on electrostatic principles, with a metal clapper oscillating between two bells at a frequency of 2 hertz. It has rung approximately 10 billion times and holds a Guinness World Record for the world's most durable battery. The exact composition of the piles remains unknown, but they are thought to be Zamboni piles.