EELS measurements of the dispersion curve of the Rayleigh wave on Ag(100) are reported along the overlineΓ- overlineX direction up to the Brillouin zone border. The comparison of the measured spectra with the theoretical predictions by Castiel et al. and Black et al. shows that the surface is not contracted in contrast with the behavior of the same face of Cu and Ni. The sign and magnitude of the change of the surface force constants are therefore shown to be related not only to the surface structure but also to the (sp)-d hybridization of the electronic states at the surface.