The plane linkage was generalized to a root-face hybrid system that composes of a planar particle system and a planar rigid body system.

A hatred that scores the face of every swallow-burrowed scarp, nourishes the root of every fruit tree, and supercedes all other loyalties and enmities.

There are two prominent muscle in on either side of the face, white, with small black spots, bead point of steel needle of a root beard.