William Herschel discovered IC 4996 on 20 Sep 1786 (sweep 594) and recorded, "Clustering stars the place taken is pretty much condensed, and contains 3 pS stars close together". He didn't assign an internal discovery number or H-designation, so this observation went unpublished, but Wolfgang Steinicke found that his offset in time and PD from 6th magnitude 34 Cygni (the next object in the sweep) matches this cluster. Steinicke also notes that soon after in the sweep he encountered M29, and just noted a "Clustering large stars" again without assigning a number.

According to Steinicke, Hugo Clemens "noticed the object on a plate taken [13 Jun 1896] for the Photographische Himmelskarte with a 10.5" f/10.5 astrograph at Potsdam Observatory." The IC credit went to Frank Bellamy, who independently discovered IC 4996 on a plate taken 13 Jun 1896 with the 13" astrograph at Radcliff Observatory in Oxford. The discovery was announced in the paper "A New Cluster in Cygnus", MNRAS 64, 662 (1904). Bellamy didn't state a position for the cluster and Dreyer's estimated position is ~25' too far north.

200/250mm - 8" (8/28/81): consists of three mag 9 stars with a string of stars to the stars, over haze, appears rich with averted.

300/350mm - 13.1" (8/25/84): ~40 stars at 144x. Rich in faint stars using averted vision.

13.1" (9/9/83): 30-40 stars at 160x, appears very rich, includes several very faint stars, elongated SSW-NNE. The brightest stars are three mag 8.5-9 stars in a tight grouping in the center.

400/500mm - 18" (8/14/04): beautiful open cluster at 225x with perhaps three dozen stars resolved in fairly poor seeing. Appears small, but rich and quite elongated SSW-NNE, ~4'x2'. Includes three bright mag 8.5-9.5 stars (ADS 13626) forming an obtuse isosceles triangle with the brightest star at the vertex. A 4th fainter star to the west forms a trapezoid with this trio. Two of the stars in the triangle are close, unequal doubles (including ß422, 9.7/10.8 at 4") and the single star has a 13th magnitude close pair nearby! The remainder of the stars in the cluster are generally mag 13 and fainter. There are sprays of stars to the north and south giving the elongated appearance. Located 1.1° SE of the Crescent Nebula and 1.7° SW of M29.

Notes by Steve Gottlieb