Rubik's family cubes of all sizes Rubik's family cubes of all sizes The original Rubik's cube was a mechanical 3×3×3 cube puzzle invented in 1974 by the Hungarian sculptor and professor of architecture Ernő Rubik. Extensions of the Rubik's cube have been around for a long time and come in both hardware and software forms. The major extension have been the availability of cubes of larger size and the availability of the more complex cubes with marked centres. The properties of Rubik’s family cubes of any size together with some special attention to software cubes is the main focus of this article. Many properties are mathematical
Singer puzzle box plus spare needles, bobbins, screws, and screwdrivers. The accessories fit into a fold-out rectangular wooden box elegantly lined with velvet. Each accessory has its own particular niche in the box, such that they will all fit together into the small space of the folded-up box. The box was invented in 1888 by John M. Griest, a Singer employee who won a US patent for the design. Singer puzzle box A Singer puzzle box is a collection of accessories for a sewing machine. Produced by the Singer Manufacturing Company during the 19th and 20th centuries, these neat and compact kits provide