[Ellipsis753]

It seems to say that these were never used and then says that they were used in the world wars? I was under the impression that they had indeed been used successfully for mines. Is this not the case?

[asdfs]

A shaft passer refers to a wheel that can rotate even if a shaft is held between spokes; the image in the wiki page shows one.

The device used in mines is somewhat similar in that it seems to allow solid objects to pass through each other, but it is not a shaft passer as it is not a wheel with "penetrable" spokes.

[foobarqux]

Allegedly

[ars_technician]

I think it's saying that they haven't been used on all of the spokes on a wheel.

They were used on the mines. http://drgoulu.files.wordpress.com/2007/03/minesweep.jpg

[jackgavigan]

I turned into doge for a moment when I looked at that image: "Wow. So simple. Very elegant. Such genius."