  We report the first direct experimental observation of scarring phenomenon in
transverse vibrational modes of a thin metal plate. The plate has the shape of
a full stadium and clamped boundary conditions. Normal modes are imaged using
time-averaged holographic interferometry, and modes corresponding to ``bouncing
ball'' and higher order periodic trajectories are found. An eikonal
approximation of the solution along classical trajectories of the stadium
including nontrivial phase shifts at clamped boundaries yields a useful
quantization condition for the observed modes.
