  A dedicated stroboscopic device was used to obtain optical spectra of the
Crab main-pulse and inter-pulse as well as the spectrum of the underlying
nebula when the pulsar is turned off. As the nebular emission is very
inhomogeneous, our ability to effectively subtract the nebular background
signal is crucial.
  No spectral lines intrinsic to the pulsar are detected. The main-pulse and
the inter-pulse behave as power laws, both with the same de-reddened index
Alpha = +0.2 +- 0.1. This value was obtained by subtracting the nebular
spectrum at the exact position of the pulsar. The underlying nebula is redder,
Alpha = -0.4 +- 0.1. Its emission lines are split into approaching (sim. -1200
km/s) and receding (sim. +600 km/s) components. The strength of emission line
components and the flux in nebular continuum vary on arcsec scale. The nebular
line and continuum intensities along the N-S slit are given.
