Yes, this is old content, but old content means a lot of people missed on it the first few times.
The first one is the Impossible Fork.
The impossible fork (Seckel 2002, p. 151), also known as the devil’s pitchfork (Singmaster) or blivet, is a classic impossible figure originally due to Schuster (1964). While each prong of the fork (or, in the original work, “clevis”) appears normal, attempting to determine their manner of attachment shows that something is seriously out of whack.
On this same graph, you can also notice 2 other impossibilities: Ambihelical Hexnut and the Tribox (with the holes in it).
The same websites gives us other mathematical and geometrical examples: the freemish crate, the baseball homeplate, impossible joinery, impossible torus, the Klein Bottle, the Penrose Stairway and finally, the Penrose triangle.
Music has also given us some examples of impossible material, more particularly composer John Stump. Here are his two masterpieces, Faerie’s Aire and Death Waltz and String Quartet No. 556(b) for Strings In A Minor (Motoring Accident). The thumbnails are scan from each piece.
You want to put what, in what?,,,,
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