Photograph of 'Praesepe' the beehive star cluster (M44), taken by Isaac Roberts using a twin telescope (20-inch reflector & 7-inch refractor) by Howard Grubb of Dublin. Taken with an exposure of 90 minutes on 13 February 1891 at his observatory & home at Crowborough, Sussex. Photograph of 'Praesepe' the beehive star cluster (M44) 1891
Positive on glass, enlarged at the National Observatory in Paris, of: New Nebula Isaac Roberts monocerotis (R.A.7h 0m, Dec S.10 degree 20') enlarged 3.4 times, scale 1mm to 24 seconds of arc, taken at Crowborough, Sussex, March 9th 1899, between sidereal time 7h1m and 9h 48m, with an exposure of 2h H7m. Positive on glass 1899
Positive on glass, enlarged at the National Observatory in Paris, of: Nebula M.94 Canum Venaticorum (R.A. 12h 46m 13.1s, Dec. N.41 degrees 39.5') enlarged 6 times, scale 1mm to 14 seconds of arc, taken at Crowborough, Sussex, on May 21st, 1903, between sidereal time 15h. 15m and 16h, 15m with an exposure of one hour Positive on glass 1903
Transparency, 10"x8", showing double open cluster in Perseus. N.G.C. 869 and 884, R.A.2h 14m. Dec.+56 degrees 40'. Isaac Roberts, Crowborough 1895, October 12. 20-inch Reflector, exposure 1h.30m. Transparency, 10"x8", showing double open cluster in Perseus. N.G.C. 869 and 884 1895
Positive on glass, enlarged at the National Observatory in Paris, of: Nebula, M.101 Ursae Majoris (R.A. 13h.59m.39s. Dec N. 54[o] 59 8') enlarged 6 times, scale 1mm to 14 seconds of arc taken at Crowborough, Sussex, 28th May, 1900 between sidereal time 14hr 36m and 17h 21m, with an exposure of 2h, 45m Positive on glass 1900
Positive on glass, enlarged at the National Observatory in Paris, of: Spiral nebula M.51 Andromedae (R.A. 0h. 37m. 17s. Dec.N.40 degrees 43.4') enlarged 3.4 times, scale 1mm to 24 seconds of arc, taken near Liverpool, December 29th 1888 between sidereal time 1h. 38m. and 5h. 45m, with an exposure of 4 hours. Positive on glass 1906