The Physiological Mechanics of Piano Technique

A device for monitoring the occupation of respective positions by team members in a game where each team member regularly changes position. It has a carrying element with a number of discrete spaces. At the spaces there can be individually provided information as to the position or team member. There is a movable element with the same number of spaces on the carrying element. The movable element carries the other of the two i.e. position or team member.