Simultaneous measurements of the P- and S- wave velocities at 1 MHz frequency as a function of temperature from -80 ¿C to 80 ¿C have been made in a Fontainebleau sandstone saturated with glycerol. We investigated 8 saturation degrees, from fully saturated to almost dry state. Generally, the velocity decreases with increasing temperature; it is large between ≈-40 ¿C and ≈40 ¿C. The velocity dispersion is attributed to viscous shear relaxation. The model of O'Connell and Budiansky modified by introducing the saturation parameter and a Gaussian distribution of crack aspect ratios is used to interpret the data. A trial and error method is used to estimate the model parameters. The model satisfactorily accounts for the data at high saturation. ¿American Geophysical Union 1991