  We report deep long-slit emission-line spectra, the line flux ratios, and
Doppler profile shapes of various bright optical lines. The low-ionization
lines (primarily [N I], [O I], [S II], and [N II]) originate in shocked knots,
as reported by many previous observers. Dust-scattered lines of higher
ionization are seen throughout the lobes but do not peak in the knots. Our
analysis of these line profiles and the readily discernible stellar continuum
shows that (1) the central star is an active symbiotic (whose spectrum
resembles the central stars of highly bipolar and young PNe such as M2-9 and
Hen2-437) whose compact companion shows a WC8-type spectrum, (2) extended
nebular lines of [O III] and He I originate in the heavily obscured nuclear H
II region, and (3) the Balmer lines observed throughout the lobes are dominated
by reflected H{\alpha} emission from the symbiotic star. Comparing our line
ratios with those observed historically shows that (1) the [O III]/H\b{eta} and
He I/H\b{eta} ratios have been steadily rising by large amounts throughout the
nebula, (2) the H{\alpha}/H\b{eta} ratio is steadily decreasing while
H{\gamma}/H\b{eta} remains nearly constant, and (3) the low-ionization line
ratios formed in the shocked knots have been in decline in different ways at
various locations. We show that the first two of these results might be
expected if the symbiotic central star has been active and if its bright
H{\alpha} line has faded significantly in the past 20 years.
