by Matthew Cobb
Here’s the explanation of the Mephisto illusion I posted earlier today… Cunning, eh?
Here’s the explanation!
October 26, 2017 • 1:30 pm
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Does he really give the explanation ?
If so I didn’t understand it.
I don’t either!
The two spirals are opposite-handed – one’s left-handed, one’s tight-handed – and fixed together.
Everybody instinctively assumed the spirals were both the same chirality.
cr
No… No he didn’t… 😂
Ah… chirality strikes again! I didn’t notice that before. I don’t have the math to explain how this works for the illusion, but it must be rather central.
Is it something like phase-shifting?
You mean it wasn’t magic?
ha! what i mean is, he said they are wound differently. one right-handed and one left. I suspect that contributes to the illusion in a way two similar-handed coils would not. any topologists around here?
Don’t need much topology. They’re opposite-handed. So as they both rotate the same way, they seem to be ‘screwing’ in different directions.
cr
I think he has to turning it in the back of his hand. So a conjuring trick. Otherwise I’m stumped.
Sigh! I mean, sub.
So klar wie Schlamm…
i think that the twist is held between the fingers and thumb in such a way that when pulling apart a force is induced that rotates the whole thing
so much for autofill in firefox!
bascule
They’re fixed together but opposite-handed.
So as they both rotate the same way, they seem to be ‘screwing’ in opposite directions.
NOBODY in the last post thought of that (I didn’t). Everybody assumed without even thinking about it that both spirals were the same chirality (e.g. both ‘right-handed’).
In fact the guy says it at 6 seconds in to this video and I still missed it till I saw the big welded-together sample at the end.
Once you realise what it is, it’s blindingly obvious to anyone familiar with screw threads, at least.
What a diabolically cunning trick.
cr
THIS is a video demonstration of the principle behind the Mephisto Spiral that everybody will understand:
That is much clearer, thanks.
I feel so stupid. Tell me if this is it: It’s his hands that are moving back and forth – not the spiral?
yeah, the hand just slides along the coil, it doesn’t grip and pull, which is what people naturally assume.
The operator should take care to obscure the ens of the coils, as soon as observers focus on them the game is up.
Can we give it up for Time Rowett, the presenter here? His Grand Illusions channel on YouTube is responsible for millions of hours of lost production hours due to his charming presentation of clever toys and gimmicks.