John Herschel discovered NGC 5188 = h3515 on 1 May 1834 and recorded "F; pL; R; glbM; 45"." His mean position (2 observations) is accurate.

400/500mm - 17.5" (6/2/00): fairly faint, moderately large, elongated 5:2 WNW-ESE, 2.0'x0.8', broad concentration. A mag 11 star is close off the WNW end [1.9' from center].

Notes by Steve Gottlieb