  The parametric variation of the eigenfrequencies of a chaotic plate is
measured and compared to random matrix theory using recently calculated
universal correlation functions. The sensitivity of the flexural modes of the
plate to pressure is used to isolate this symmetry class of modes and simplify
the data analysis. The size of the plate is used as the external parameter and
the eigenvalues are observed to undergo one or two oscillations in the
experimental window. The correlations of the eigenvalues are in good agreement
with statistical measures such as the parametric number variance, the velocity
autocorrelation, and the intralevel velocity autocorrelation derived for the
Gaussian Orthogonal Ensemble of random matrix theory. Our results show that the
theory can be also applied to wave systems other than quantum systems.
