William Herschel discovered NGC 1684 = H II-528 = h334 on 1 Feb 1786 (sweep 518) and noted "The 2nd [with NGC 1682], F, S, lbM." His position is 40 seconds of time too far east (same error as NGC 1682 = II-527). John Herschel made two observations at Slough, recording on 24 Nov 1827 (sweep 109), "pB; R; bM; has a *7m 45? sp; very well observed." His position was accurate, though I'm surprised he missed nearby NGC 1682. The field was observed 9 times at Birr Castle. Because of the confusion with WH's positions as well as the identifications at Birr Castle, JH assigned 3 GC designations -- 920, 921 and 924. Dreyer sorted this out and combined the entries in the NGC.

400/500mm - 17.5" (12/23/89): fairly faint, fairly small, oval ~E-W, broadly concentrated halo. Brightest of four with NGC 1682 3' W, NGC 1683 6' NW and NGC 1685 9' N. Mag 8.0 SAO 131557 lies 3' SSW.

Notes by Steve Gottlieb