Double cone

    Caption: Double cone.

    A precession is a motion where a body's rotational axis sweeps out a cone or a double cone.

    Speaking of cones:

      "Chief, I demand the Cones of Silence."---Maxwell Smart---you had to have been there in the 1960s.

    Credit/Permission: Lars H. Rohwedder (AKA User:RokerHRO), 2006 / Public domain.
    Image link: Wikimedia Commons: File:DoubleCone.png.
    Local file: local link: double_cone.html.
    File: Mechanics file: double_cone.html.