Spiral for creating an optical illusion comprises a central part with a ball suspended on a cord, and an aerodynamic device attached to the suspension cord

摘要

Spiral (6) comprises a central part with a ball (7) suspended on a cord (3) which when rotated gives the appearance that the ball moves upward and downward. An aerodynamic device (1) is attached to the suspension cord. Preferred Features: The aerodynamic device has at least one, preferably three or more blades (hemispheres (5)) and a height-adjustable slide.