  We investigate various properties associated with the tilt of isolated
magnetic bipoles in magnetograms taken at the solar surface. We show that
bipoles can be divided into two groups which have tilts of opposite signs, and
reveal similar properties with respect to bipole area, flux and bipolar moment.
Detailed comparison of these physical quantities shows that the dividing point
between the two types of bipoles corresponds to a bipole area of about 300
millionths of the solar hemisphere (MHS). The time-latitude distribution of
small bipoles differs substantially from that for large bipoles. Such behaviour
in terms of dynamo theory may indicate that small and large bipoles trace
different components of the solar magnetic field. The other possible viewpoint
is that the difference in tilt data for small and large bipoles is connected
with spectral helicity separation, which results in opposite tilts for small
and large bipoles. We note that the data available do not provide convincing
reasons to prefer either interpretation.
