 The values of the queen and rook are considerably augmented by their greater range – with two rooks or a queen and rook unobstructed on the same ring being especially powerful – while those of the bishop and knight are diminished; for example, on an 8×8 board two minor pieces are held to be stronger than one rook, but on a circular board the rook is considerably stronger.This can be easily seen by just counting the number of squares an unobstructed piece is able to attack on an orthodox and a circular board