| These so-called 'Non Transitive Dice' (Magic Dice) demonstrate a probability that violates common sense and traps the unwary. |
| | Another variation on Non Transitive Dice, this time based on a set of three dice. |
| | A three-sided mirror kaleidoscope with a fivefold symmetry axis |
|
| This Tippe Top has an unexpected extra trick... |
| | A Ring Dial was a cutting edge scientific instrument in its time, which is about 500 years ago! |
| | If you spin it fast enough, it will turn completely upside down, spinning on its stem. |
|
| Whichever way you roll them, their width is always the same, although they are not spheres! |
| | A beautiful physical version of Dudeney's Dissection, where the 4 pieces are hinged, so that you can transform one shape into the other. |
| | 'Napier's Bones' is an early calculating device that allowed the user to carry out multiplication and division. |
|
