Lewis Swift discovered NGC 6224 = Sw. IX-66, along with NGC 6225, on 15 Jun 1887 and recorded "eeeF; vS; lE; pB * nr north both in trap; eee diff; np of 2 [with NGC 6225]." His RA is 9 seconds too large (similar offset as NGC 6224). The discovery was sent directly to Dreyer, reported as list VI in the NGC, but not published until list IX.

400/500mm - 17.5" (7/1/89): faint, very small, round, small bright core. A mag 11 star is 1.6' N. Forms a pair with NGC 6225 5.4' S.

Notes by Steve Gottlieb