first rank (e.g. queen, , ), and ranks by the numbers 1 to 8 from each player's point of view, depending on the move being described. This method is no longer commonly used. FIDE stopped using descriptive notation in 1981. ICCF numeric notation assigns numbers to both files and ranks, with rank 1 being the one closest to the player with the white pieces. The file leftmost to the white player (a in algebraic notation and QR in descriptive notation) is file one and the rightmost to them (h in algebraic notation and KR in descriptive notation) is file eight. Variant boards Variant chessboard shapes and sizes go back to the Persian origins of the game in the 10th century, when the book Muraj adh-dhahab (Board of the Gods) described six different variants of chess, including circular and cylinder chess. Due to the widespread creation of new variants, a wide variety of sizes can be found. Gliński's hexagonal chess utilises a board with 91 hexagonal spaces of three different colours. One innovation of the 13th century was the cylindrical board for use in cylinder chess. The board used for the Persian Tamerlane chess is one of the first recorded variant chessboards, with eleven columns by ten rows along with two citadels. Each player has a citadel to the right of their second rank, which may be occupied by the opponent's king, in which case that opponent may declare a draw. In 1617, Pietro Carrera proposed a variant that received his name, Carrera's Chess, with a 10×8 board, later used in other variants such as Capablanca chess and Gothic Chess. Other sizes, with ten rows by ten columns, are used in Omega Chess and Grand Chess; Omega Chess has four additional squares, one in each corner of the board. Los Alamos chess uses a smaller 6×6 board. Japanese shogi uses a board with nine columns by nine rows. The board of Chinese xianqi consists of nine columns by ten rows; here, the pieces are placed on the intersections of the lines that divide the squares, rather than within the squares themselves. Each player has a 3×3 palace in the central three columns and the closest three rows, within which the player's general and advisors must stay. Between the central two rows is a river that the elephant cannot cross and past which the soldier increases in strength. A similar board without