Extensive research into the art of turning in relation to chessmen led Franz Josef Lang to discover designs by the Munich master turner, Michael Edel. He was active during the first third of the 19th century, and published his designs in 1839. In his theory concerning the construction of the pieces he wrote that an ivory chess set, if ivory, should consist of '266 pieces, the threads having equal calibre.' See Franz Josef Lang, Chess Sets by German Turners, Chess Collectors International, Vol. 2, November 1991, No. 3.