We have measured the extensional modulus (ratio of stress to strain, E) and the fractional energy loss per radian (Q-1E) as functions of frequency in cylindrical samples of two solids: a room-dry sandstone (Berea) and an acrylic plastic (Lucite). In the seismic frequency range (0.1--100 Hz), Q-1E for the sandstone is constant, while the sandstone modulus follows a power law of frequency, E(f)∝[(f)/(f0)>2 tan-1(Q-1E)/&pgr; allowing Q-1E to be independently estimated from the slope of log E versus log f. In the same frequency range, Q-1E for the acrylic plastic is not constant but exhibits a slight relaxation peak centered about 2 Hz. In this case Q-1E can be estimated from the derivative, d log E/d log f, i.e., the above power law appears to hold independently at each point in the frequency domain even when Q-1E is varying. ¿ American Geophysical Union 1990