Little is known about the early history of interlocking puzzles, but they were certainly produced both in Asia and Europe as early as the 18th century. Six-piece burrs were shown as early as 1803 in the Bestelmeier Toy catalogs. But it wasn't until Edwin Wyatt published Puzzles in Wood in 1928 that a book devoted to many interlocking puzzles was available. Puzzles of this type used to be known as "Chinese" puzzles, probably because they were mass-produced in the Orient since the early 1900s, but there does not appear to be any evidence that the idea originated there. Nowadays they are commonly referred to as "burr" puzzles. Wyatt introduced the term because the puzzles looked like a seed burr.