Berechenbar (Napier’s Bones)
A laser-cut wood tool for multiplying large numbers. The initial state shows a regular times-table from 1 to 9, but by sliding the rods it is possible to multiply large numbers with little effort.
Made in laser-cut wood by Jean-Claude Constantin. Jean-Claude Constantin lives in Germany, where he designs and manufactures many different laser-cut wood puzzles, as well as metal puzzles and magic tricks.