Adam Savage Meets David Jones's DREADCO “Perpetual Motion” Machine

In the 1980s, David Jones, who described fanciful inventions in his “Daedalus” column in New Scientist and later Nature, built a series of fake “perpetual motion machines” which he challenged others to figure out what kept them going. (Among the inventions of Daedalus were his prediction of hollow carbon molecules in 1966, long before the discovery of buckminsterfullerene in 1985, 3D printing in 1974, and a space elevator in 1964. The columns are collected in The Inventions of Daedalus and The Further Inventions of Daedalus, both now out of print.)

After David Jones’s death in 2017, a collection of his work was left to Sir Martyn Poliakoff, who donated the “perpetual motion machine” it included to the Royal Society, where it now figures in their collection. Along with the machine was a envelope containing the secret of its operation, which will remain sealed for thirty years.

Many have tried to discern the disguised workings of Daedalus’s perpetual motion machines, but I’ve heard that only one person ever suggested the right answer to its creator. The secret is now kept in an envelope in the archive of the Royal Society, to remain closed for the next 30 years, with the exception of those entrusted with its maintenance – it turns out that the machine may require an occasional nudge to keep it going.

How do you think it works?


In this series of videos, you can see the relative speed decrease in a period of approx 1yr.

This is taken shortly after Jones’ death: Perpetual Motion by Daedalus - YouTube

And this is filmed in 2018: Perpetual Motion Machine - Periodic Table of Videos - YouTube

Compare that with clearly faster speed shown in Adam Savage’s video, where the curator sort of casually mentions that the machine has been “taken for maintenance”.

Reddit leans towards a slowly decompressing spring (source)

That’s plausible - would be the equivalent of a scaled-up simplified mechanical watch movement with a 2-3 years power reserve. No need for batteries, etc. Keeping the insides more or less sealed from the outside will ensure minimal dust contamination of the wheel bearings, which in turn will minimize friction.


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