  A recent re-analysis of EGRET data by Dixon et al. has led to the discovery
of a statistically significant diffuse $\gamma$-ray emission from the galactic
halo. We show that this emission can naturally be accounted for within a
previously-proposed model for baryonic dark matter, according to which dark
clusters of brown dwarfs and cold self-gravitating $H_2$ clouds populate the
outer galactic halo and can show up in microlensing observations. Basically,
cosmic-ray protons in the galactic halo scatter on the clouds clumped into dark
clusters, giving rise to the observed $\gamma$-ray flux. We derive maps for the
corresponding intensity distribution, which turn out to be in remarkably good
agreement with those obtained by Dixon et al. We also address future prospects
to test our predictions.
