John Herschel discovered NGC 1804 = h2742 on 3 Nov 1834 and described "F (?), R, bM (Thick haze in sky)". On a second sweep his description reads "F, S, R, 30". Shapley and Lindsay (1963) give a diameter of 25'' and remark "few stars, partly condensed."

600/800mm - 24" (11/18/12 - Magellan Observatory, Australia): very small bright knot, ~25"-30" diameter, with four or more mag 12-14.5 stars resolved including three on a NW to SE line. Tightly packed into a very high surface brightness glow. S-L 180 lies 4' NE and appeared as a fairly faint, moderately large, round, 0.5' diameter, soft glow with no resolution.

Notes by Steve Gottlieb