He was first to recognize that the fixed link of a mechanism was kinematically the same as the movable links.
kinematics kin·e·mat·ics (kĭn'ə-māt'ĭks)
The branch of mechanics dealing with the study of the motion of a body or a system of bodies without consideration given to its mass or the forces acting on it.
The branch of physics that deals with the characteristics of motion without regard for the effects of forces or mass. Compare dynamics.