  This talk deals with two topics in multiparticle dynamics investigated by
means of the DELPHI detector at LEP. Related to the first topic, we have used
the data collected at 183 GeV to measure the average charged particle
multiplicity in $e^+e^- \to b\bar{b}$ events. The result is remarkably in
agreement with QCD predictions, while it is more than two standard deviations
larger than calculations assuming that the multiplicity accompanying the decay
of a heavy quark is independent of the mass of the quark itself. The second
topic deals with a recent theoretical model by Andersson et al., in which soft
gluons order themselves in the form of a helix at the end of the QCD cascades.
In our data at the Z peak, we have found no evidence for such an effect.
