Experiments with a rubber tube model of the aorta have demonstrated the presence of longitudinal waves in the wall of the tubing. This mode of vibration was predicted by Lamb from the theoretical considerations, but has not previously been described. The characteristics of “impact waves” in arteries and of the longitudinal mural waves in the model appear to be similar. Longitudinal waves undoubtedly influence the arterial pulse contour. Theoretically, the damping coefficient for them is the same as that for radial waves.