A mechanical puzzle is a puzzle presented as a set of mechanically interlinked pieces.
The oldest known mechanical puzzle comes from Greece and appeared in the 3rd century BC. The game consists of a square divided into 14 parts, and the aim was to create different shapes from these pieces. This is not easy to do. (see Ostomachion loculus Archimedius)
In Iran “puzzle-locks” were made as early as the 17th century AD.
The next known occurrence of puzzles is in Japan. In 1742 there is a mention of a game called “Sei Shona-gon Chie No-Ita” in a book. Around the year 1800 the Tangram puzzle from China became popular, and 20 years later it had spread through Europe and America.
The company Richter from Rudolstadt began producing large amounts of Tangram-like puzzles of different shapes, the so-called “Anker-puzzles” in about 1891.
In 1893, , using the pen name "Professor Hoffman", wrote a book called Puzzles; Old and New. It contained, amongst other things, more than 40 descriptions of puzzles with secret opening mechanisms. This book grew into a reference work for puzzle games and modern copies exist for those interested.
The beginning of the 20th century was a time in which puzzles were greatly fashionable and the first patents for puzzles were recorded. The puzzle shown in the picture, made of 12 identical pieces by W. Altekruse in the year 1890, was an example of this.
With the invention of modern polymers manufacture of many puzzles became easier and cheaper.
In this category, the puzzle is present in component form, and the aim is to produce a certain shape. The Soma cube made by Piet Hein, the Pentomino by Solomon Golomb and the aforementioned laying puzzles Tangram and “Anker-puzzles” are all examples of this type of puzzle. Furthermore, problems in which a number of pieces have to be arranged so as to fit into a (seemingly too small) box are also classed in this category.
The image shows a variant of Hoffman's packing problem. The aim is to pack 27 cuboids with side lengths A, B, C into a box of side length A+B+C, subject to two constraints: