  We show that grains can be efficiently aligned by interacting with a subsonic
gaseous flow. The alignment arises from grains having irregularities that
scatter atoms with different efficiency in the right and left directions. The
grains tend to align with long axes perpendicular to magnetic field, which
corresponds to Davis-Greenstein predictions. Choosing conservative estimates,
scattering efficiency of impinging atoms and conservative ``degree of
helicity'', the alignment of helical grains is much more efficient than the
Gold-type alignment processes.
