Thomas D. Rossing
Phys. Dept., Northern Illinois Univ., DeKalb, IL 60115
Daniel A. Russell
Graduate Prog. in Acoust., Penn State Univ., University Park, PA 16802
Several old [Lord Rayleigh, Philos. Mag. 13, 316--333 (1907)] and new [Rossing et al., Am. J. Phys. 60, 620--626 (1992)] demonstration experiments using tuning forks are illustrated. These include nonlinear motion of the stem, radiation of the second harmonic, effect of a baffle, and the behavior of bent and loaded forks.