So some years ago I read a story that included a "sword in the stone" bit and it was explained that the sword was held in place by electromagnets that could be released when "the one" tried to pull the sword out.

I don't remember how integral to the story this bit was (it might have been just an aside about how the current king had been picked). I also don't remember if this was part of a full novel or just a short story. I think time travel was involved as the setting was "fantasy-esque" and the whole electricity/magnet connection was obviously an anachronism.

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    As a side note: This sword scheme was once used as a key plot point in an episode of the now-cancelled TV program 'Banacek'.
    – PMar
    Commented Mar 13, 2019 at 17:21
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    Oddly related recent WorldBuilding question: worldbuilding.stackexchange.com/q/141322/702
    – jpmc26
    Commented Mar 14, 2019 at 1:22
  • It also appears in the Scorpion series (one episode occurs in a medieval festival and someone acts as Arthur releasing the sword but a genius notices and reveals that there's an electromagnet maintaining it)
    – Rafalon
    Commented Mar 14, 2019 at 7:50
  • Another side note: the trick (or one very much like it) works well. I was the adult from the audience of a magic show who couldn't lift a box a child could. It was held down with a large electromagnet in a stand that was weighted down with my own weight, and had a steel plate in the bottom. I'm a scientist/engineer so I spotted it despite the well-disguised switch - but of course I didn't let on.
    – Chris H
    Commented Mar 14, 2019 at 12:13
  • @jpmc26 I posted an answer there, but wanted to track down the source of my inspiration in order to improve my answer. Hence this question.
    – aslum
    Commented Mar 14, 2019 at 14:46

3 Answers 3


This may be "Once and Future" by the late Terry Pratchett, first published in Camelot in 1995. A time-travelling historian named "Mervin" gets stranded in an anachronism stew that mostly matches Arthurian legend, and he reproduces the sword-in-a-stone bit in order to get a king who will follow his advice for advancing technology.

All the mechanical ways of doing it I had to rule out. That left electricity. Strange thing is, it's a lot easier to make a crude electrical generator than a crude steam engine. The only really critical things are the bearings.

And the copper wire.

And then, when the sword is pulled, Mervin finds out how this Albion is different from ours:

Uther had a daughter in this world.

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    I think this is it... I'll double check and then mark correct if so!
    – aslum
    Commented Mar 13, 2019 at 16:52

It's been a long time since I read them, but I believe Merlin used a lodestone (magnet, but not electromagnet) in this way in A. A. Attanasio's The Dragon and the Unicorn series. Sadly I can't find a ready summary now.

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    Can confirm. That series consistently treats electromagnetic phenomena as a type of magic, starting with the identification of the "Storm Tree" (Yggdrasil) with the earth's magnetic field.
    – zwol
    Commented Mar 13, 2019 at 21:36

It also showed up in Interstellar Patrol II the Federation of Humanity, by Christopher Anvil. It wasn't a time-travel story, but there was absolutely a sword in a stone that was being used to determine a ruler, and people mucking about with magnets to mess with the situation.

(excerpt link)

  • I thought of this one, too, it does seem to fit
    – Megha
    Commented Mar 15, 2019 at 0:36

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