Coin of the Realm

I only asked my daughters to bring me back one souvenir from their trip to the U.K., if they were able to find it without too much effort. They were.

It's a 2-pound coin, worth about $4 U.S. I wanted this coin for two reasons: first, because the rings of gears and stylized circuit board make it an unusual tribute to technology, capturing progress from the early Industrial Age to the Electronic Era. I further learn online that the innermost circle's subtle pattern of whorls around a rudimentary wheel is meant to symbolize the Iron Age, while the outermost ring of criss-crossed lines is meant to symbolize the Internet. Neither is obvious to me but I appreciate the effort. An inscription on the edge of the coin quotes Isaac Newton: "Standing on the shoulders of giants." (The "heads" side is a portrait of Queen Elizabeth.) Not many governments acknowledge the importance of science and technology on their money like that.

Second, there is something about the coin I find irresistible. I'll say no more for now; I leave the reason for my fascination as a puzzle for the reader. All the necessary clues are in the image above. I'll update this post in a couple of days to explain.

UPDATE, August 7: Thanks for commenting and playing along. Your answers are better than mine, which I hope isn't too disappointing.

What I love about the two-pound coin--the quality that made me have to have it--are the 19 interlocked gears in that ring. Any odd number of gears arranged like that would be unable to turn (the size of the gears is irrelevant, assuming their teeth mesh up). Every gear turns adjacent gears in the opposite direction, alternating clockwise, counter-clockwise, etc.:

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Turning the top gear clockwise (red) moves the gears next to it counter-clockwise (blue)....

Go all the way 'round the ring and, with an odd number of gears, you hit a point where two adjacent gears want to turn the same direction. Won't work. The whole thing is locked up.

Examples of true irony (as opposed to the Alanis Morissette kind) are hard to find in life and I treasure them when I do. I think the government of the United Kingdom commemorating the formidable triumph of the Industrial Age with a machine that can't possibly
work--can't even move--qualifies as ironic. At least, it's the most fun I've had for $4 lately.

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