  This is the first paper presenting our long-term project aimed at studying
the nature of bulges through the analysis of their stellar population
gradients. We present deep spectroscopic observations along the minor axis and
the data reduction for a sample of 32 bulges of edge-on spiral galaxies. We
explain in detail our procedures to measure their dynamical parameters
(rotation curves and velocity dispersion profiles) and line-strength indices,
including the conversion to the Lick/IDS system. Tables giving the values of
the dynamical parameters and line-strength indices at each galactocentric
radius are presented (in electronic form) for each galaxy of the sample. The
derived line-strength gradients from this dataset will be analyzed in a
forthcoming paper to set constraints on the different scenarios for the
formation of the bulges.
