The Clarendon Dry Pile at Oxford University is a strange, candelabrum-looking device under a tall glass dome. The Guinness Book of World Records lists it as the “world’s most durable battery,” and credits it with “ceaseless tintinnabulation.”
The “tintinnabulation” refers to the fact that the Clarendon Dry Pile is an electric bell-ringer. Its design involves two ancestral batteries attached to two metal bells, and a tiny metal ball that swings back and forth between the bells, striking them at a rate of about two times per second.
“Ceaseless” is an exaggeration, but not much of one. The Clarendon Dry Pile has been ringing — allegedly without interruption, although that’s almost impossible to believe — for 172 years. The bells have been struck approximately 10 billion times.
In other words, it’s a battery-powered alarm clock with no “off” switch that has been ringing since 1840.
The Clarendon Dry Pile wasn’t really built as a scientific experiment, although it was cited as evidence in early debates about the nature of electrical attraction and repulsion. It was more along the lines of a “demonstration,” an apparatus designed to stimulate wonder, and help legitimize the new science of electricity.
In fact, the Clarendon Dry Pile was based on an 18th century design by Benjamin Franklin, whose “Franklin bells” magically rang when connected to a Leyden jar, wowing crowds on both sides of the Atlantic.
The composition of the two batteries that power the Clarendon Dry Pile is a subject of speculation, but the prevailing theory is that they’re cylinders made of alternating layers of metal foil and paper coated with manganese dioxide, that were then dipped, like a chocolate banana, in molten sulfur to seal out moisture.
Here’s how the device works. The little metal ball is attracted to one of the charged bells and strikes it. The instant the ball touches the bell, it becomes electrostatically charged by the bell’s battery. The ball is immediately repulsed and swings away. As it nears the opposite bell, it finds itself in the grip of a new attraction. But the moment it strikes that bell, it takes on a new electrostatic charge, and is instantly repulsed.
Thus, an endless cycle of attraction and repulsion drives the ball back and forth between the bells, like a clapper.
And no, the Clarendon Dry Pile isn’t an example of a perpetual motion machine, although there have been countless imitators that claimed to generate more energy than they consumed. Eventually, the two batteries will die, and the little metal ball will cease to tintinnabulate.
Sad, I know, but inevitable.
It’s amazing that the science and technology of the early 19th century were capable of producing a battery that is closing in on its dodransbicentennial (sorry, I just had to slip that one in there).
But equally amazing is the fact that this simple, elegant device has found a quiet shelf to sit on for nearly 175 years. Think about the civil stability that implies! True, Oxford University has been in existence, in one form or other, since the year 1096, which puts the longevity of the Clarendon Pile into perspective.
But the last 172 years have been tumultuous ones indeed. There’s something very moving about the thought of that tiny bell ringing steadfastly through the convulsions of the Industrial Revolution; the American Civil War; war and social upheaval in Europe and in her colonies; the Great War; the Russian Revolution; the Second World War; the Cold War.
There’s another unrelated, but even older experiment I’d like to mention, one that has outlasted all of these human disasters and then some, and which, like the Clarendon Dry Pile, has swung back and forth countless times over the centuries: the United States of America.
Of course, our democracy is a true experiment, not a demonstration. No one knows whether our civilization will be capable of weathering all of the manmade and natural disasters that the future has to offer. Perhaps, like the Clarendon Dry Pile, we’re living on borrowed time.
But in this election year, as both sides crank up the volume and try to make the case that their guy is the only one who can save our nation from certain destruction, I’d like to take a moment to praise the design of the American experiment, which, energized by the genius of countless generations of citizens, has absorbed the seemingly mortal blows of slavery, secession, civil war, and world war, and somehow managed to ring on.
A toast then, to our imperfect union: may our heads stay cool; our choices be wise, and then, when the political furor dies down, as it inevitably will, our tintinnabulation be ceaseless!
This column was published in the Perry Co Times on 12 January 2012
For more information, please contact Mr. Olshan at writing@matthewolshan.com
