Max Wolf discovered IC 3546 = W. IV-222 on a Heidelberg plate taken 23 Mar 1903. He reported "F, S, lE 150°." It was also discovered on plates taken with the Crossley reflector in 1898-1900, but not reported until 1908 (Publications of Lick Observatory, Vol VIII) as #513 of 744 new nebulae. Keeler wasn't mentioned in the IC II as it was already being published.

400/500mm - 17.5" (5/13/88): very faint, very small, roundish. Forms the east vertex of an equilateral triangle with two mag 15 stars 1.3' WSW and 1.3' WNW. Located 17' NW of NGC 4565, though lies far in the background (~300 million l.y.)

17.5" (5/10/86): faint, small, roundish at 222x.

Notes by Steve Gottlieb