Sam Loyd’s 1903 Eighth Book of Tan explores the world of tangrams, the pastime of constructing specified shapes from a given set of seven pieces:

The book includes a few “paradoxes,” two of which I’ve mentioned here before. But here’s another:

“The seventh and eighth figures represent the mysterious square, built with seven pieces; then with one corner clipped off, and still the same seven pieces employed.”

The book includes no solution. The square on the left is just the regular “block” formation above. But if anyone has discovered how Loyd produced a “clipped” square using the same seven pieces, I haven’t been able to find it.

12/22/2020 UPDATE: Reader Alon Shaham came up with this solution:

Here the seven pieces are used to make both figures, rather than each figure separately. Arguably Loyd’s description is artfully ambiguous. (Thanks also to reader Andrew Davison.)