James Dunlop discovered NGC 1261 = D 337 = h2517 on 28 Sep 1826 with his 9" reflector from Parramatta and described "a very bright round nebula, about 1.5' diameter, pretty well defined and gradually bright to the centre. A small star north following." No mention is made of resolution, though it should have been possible (brightest stars mag 13.5).

JH observed the cluster twice, first describing it on 5 Dec 1834 as a "globular, bright; large; irregularly round; 2.5' diameter; all resolved into equal stars 14 mag. Has a star 9th mag 45? N.f. 3' distant." On his second sweep he logged "pretty bright; round; very gradually brighter in the middle; 3' across; resolved into stars of 15th magnitude. A very faint nebula (??) precedes." There is a close pair of extremely faint galaxies southwest of the globular, but I doubt Herschel could have picked these up.

400/500mm - 20" (7/8/02 - Magellan Observatory, Australia): at 212x, the resolution was a bit better in the halo than with the 18", but the blazing core was still unresolved.

Notes by Steve Gottlieb