E.E. Barnard discovered IC 4688 visually on 4 Jun 1888 with the 12-inch refractor at Lick Observatory. He noted "A very faint nebula, diffused, not large." "It is pretty close p a 12 mag star. This pointing with low power." The discovery was communicated directly to Dreyer.

600/800mm - 24" (7/15/15): fairly faint, roundish, 1.0' diameter, fairly low surface brightness, no noticeable central brightening. Situated in a rich star field. IC 4691 lies 11' NE.

Notes by Steve Gottlieb