oyal Society.
1879 Michelson's experiments on the velocity of light.
1879 Publication of Gould's _Uranometria Argentina_.
1879, November Observations of the spectra of sun-spots begun at
South Kensington.
1879, Dec. 5 Abney's map of the infra-red solar spectrum presented
to the Royal Society.
1879, Dec. 18 Ultra-violet spectra of white stars described by
Huggins.
1879, Dec. 18 Communication of G. H. Darwin's researches into
the early history of the moon.
1880, Jan. 31 Discovery at Cordoba of a great southern comet.
1880 Conditions of Algol's eclipses determined by Pickering.
1880 Pickering computes mass-brightness of binary stars.
1880, Sept. 30 Draper's photograph of the Orion nebula.
1880 The bolometer invented by Langley.
1881, Jan. 20 Communication of G. H. Darwin's researches into the
effects of tidal friction on the evolution of the
solar system.
1881 Langley's observations of atmospheric absorption on
Mount Whitney.
1881, June 16 Perihelion of Tebbutt's comet.
1881, June 24 Its spectrum photographed by Huggins.
1881, June Photographs of Tebbutt's comet by Janssen and Draper.
1881, Aug. 15 Retirement of Sir George Airy. Succeeded by Christie.
1881, Aug. 22 Perihelion of Schaeberle's comet.
1881 Publication of Stone's Cape Catalogue for 1880.
1882 Struve's second measures of Saturn's ring-system.
1882 Newcomb's determination of the velocity of light.
Resulting solar parallax = 8.79".
1882 Correction by Nyren of Struve's constant of aberration.
1882, March 7 Spectrum of Orion nebula photographed by Huggins.
1882, May 17 Total solar eclipse observed at Sohag in Egypt.
1882, May 27 Sodium-rays observed at Dunecht in spectrum of
Comet Wells.
1882, June 10 Perihelion of Comet Wells.
1882, Sept. 17 Perihelion of Great Comet. Daylight detection by Common.
Transit observed at the Cape.
1882, Sept. 18 Iron lines identified in spectrum by Copeland and
J. G. Lohse.
1882, September Photographs of comet taken at the Cape Observatory,
showing a ba