William Herschel discovered NGC 6517 = H II-199 = h3719 on 16 Jun 1784 (sweep 228) and logged "pB, pL, R, bM, r and the brightness diminishing gradually." JH made two observations, first recording it (sweep 591) as "globular cluster; F; R; psbM; 90"; r; with left eye I discern the stars in it."

200/250mm - 8" (5/21/82): faint, small, brighter core, no resolution.

400/500mm - 17.5" (6/8/91): fairly faint, small, irregularly round, 2' diameter. The faint halo is slightly elongated SSW-NNE and increases to a small bright core. No resolution at 280x.

600/800mm - 24" (7/30/16): at 260x, moderately bright, round, 2.5'-3' diameter, well concentrated with a brighter, round core that increases to the center. A little lively but no definite resolution. The cluster appeared clumpy at 432x but only a couple of star were at the edge of visibility. At 500x, the nucleus was very clumply several extremely faint stars started to resolve (V tip magnitude = 16.0).

Notes by Steve Gottlieb