An empirical relation is given for the saturation velocity of a domain wall in a bubble domain garnet material. The relation is

, where

is the saturation velocity, γ the gyromagnetic ratio,

the saturation magnetization, A the exchange constant and K
uthe uniaxial anisotropy constant. The relation provides a close approximation for a wide range of experimental data. Comparisons between experimental data and theoretical data are made. A possible interpretation of the empirical relation is given.