  The old question of rotational braking of Ap Si stars is revisited on the
empirical side, taking advantage of the recent Hipparcos results. Field stars
with various evolutionary states are considered, and it is shown that the loose
correlation between their rotational period and their surface gravity is
entirely compatible with conservation of angular momentum. No evidence is found
for any loss of angular momentum on the Main Sequence, which confirms earlier
results based on less reliable estimates of surface gravity.
  The importance of reliable, fundamental Teff determinations of Bp and Ap
stars is emphasized.
