William Herschel discovered NGC 4504 = H II-771 = h1398 on 20 Mar 1789 (sweep 913) and noted "pB, iF, mbM, easily resolvable." John Herschel made a single observation from the Cape of Good Hope and logged "vF; L; lE; gvlbM; 2' l by 100" broad."

400/500mm - 17.5" (2/28/87): fairly large, almost even surface brightness, slightly elongated, very weakly concentrated core. Two mag 14.5-15 stars are off following end 1.4' NE and 2.1' ESE of center.

Notes by Steve Gottlieb