Woodwork Rattleback: prefers to spin counter clockwise- If spun clockwise, a complicated combination of friction, precession, and instability induced vibrations transforms the rotational energy into into rattling (energy of oscillations) and then into rotational energy in the opposite direction. This behavior is related to an asymmetry in weight along the left/right symmetry axis- the dark wood is Apple which has twice the density of the light colored Basswood(Linden). This asymmetry in weight i