  We decompose the luminosity function of Galactic globular clusters into a sum
of the orthogonal Gauss-Hermite functions. This method quantifies the
asymmetric third-order ($h_3$) and symmetric fourth-order ($h_4$) terms of the
distribution while minimizing the effect of outliers in the data. For 138
Galactic globulars we obtain $<M_V>=-7.41\pm0.11$, $\sigma(M_V)=1.24$ mag,
$h_3=0.02\pm 0.05$, and $h_4=0.06 \pm 0.05$, {\em i.e.\/} the core of the
distribution does not differ significantly from a Gaussian. For a
low-metallicity subsample of 103 globular clusters with $[Fe/H]<-0.8$, we find
$<M_V>=-7.48\pm0.11$, $\sigma(M_V)=1.08$ mag, $h_3=0.05 \pm 0.05$, and
$h_4=0.13 \pm 0.05$.
