Spectrophotometric Studies of Gaseous Nebulae. XVIII. The Bright, Intermediate-Excitation Planetary NGC 6210
The amorphous planetary NGC 6210 has a sufficiently high surface brightness so that its spectrum may he studied in some detail. Mount Wilson and Lick coude' plates combined with photoelectric photometry yield intensities of 122 lines of ions of H, He 1, He ii, C ii, C iii, N iii, 0 ii, [0 ii}, 0 iii, [0 iiij, [F iv}? Ne ii, [Ne iiij, Mg ii, Si iv, [S ii], [S iiij, [Ar iv], and [Fe v].