1862 Solar hydrogen-absorption recognised by ngstrom.

1862, Jan. 31 Discovery by Alvan G. Clark of the companion of Sirius.

1862 Foucault determines the sun's distance by the velocity of light.

1862 Opposition of Mars. Determination of solar parallax.

1862 Completion of _Bonner Durchmusterung_.

1863 Secchi's cla.s.sification of stellar spectra.

1863 Foundation of the German Astronomical Society.

1864, March 5 Rotation period of Mars determined by Kaiser.

1864 Huggins's first results in stellar spectrum a.n.a.lysis.

1864, Aug. 5 Spectroscopic examination of Tempel's comet by Donati shows it to be composed of glowing gas.

1864, Aug. 29 Discovery by Huggins of gaseous nebulae.

1864 Value of 91,000,000 miles adopted for the sun's distance.

1864 Croll's explanation of glacial epochs.

1864, Nov. 23 Death of Struve.

1865, Jan. 4 Spectroscopic observation by Huggins of the occultation of Eta Piscium.

1865, Jan. 16 Faye's theory of the solar const.i.tution.

1865 Kew results published.

1865 Zollner argues for a high temperature in the great planets.

1866 Ident.i.ty of the orbits of the August meteors and of comet 1862 iii. demonstrated by Schiaparelli.

1866 Delaunay explains lunar acceleration by a lengthening of the day through tidal friction.

1866, March 4 Spectroscopic study of the sun's surface by Lockyer.

1866, March 12 New star in Corona Borealis detected by Birmingham.

1866, October Schmidt announces the disappearance of the lunar crater Linne.

1866, Nov. 13 Meteoric shower visible in Europe.

1867 Period of November meteors determined by Adams.

1867, Aug. 29 Total solar eclipse. Minimum sun-spot type of corona observed by Grosch at Santiago.

1867 Discovery of gaseous stars in Cygnus by Wolf and Rayet.

1868, February Principle of daylight spectroscopic visibility of prominences started by Huggins.

1868, Aug. 18 Great Indian eclipse. Spectrum of prominences observed.

1868, Aug. 19 Janssen's first daylight view of a prominence.

1868, Oct. 26 Lockyer and Janssen independently announce their discovery of the spectroscopic method.

1868 Doppler's principle applied by Huggins to measure stellar radial movements.

1868 Publication of ngstrom's map of the normal solar spectrum.

1868 Spectrum of Winnecke's comet found by Huggins to agree with that of olefiant gas.

1869, Feb. 11 Tenuity of chromospheric gases inferred by Lockyer and Frankland.

1869, Feb. 13 Huggins observes a prominence with an "open slit."

1869, Aug. 7 American eclipse. Detection of bright-line coronal spectrum.

1870 Mounting of Newall's 25-inch achromatic at Gateshead.

1870 Proctor indicates the prevalence of drifting movements among the stars.

1870 A solar prominence photographed by Young.

1870, Dec. 22 Sicilian eclipse. Young discovers reversing layer.

1871, May 11 Death of Sir J. Herschel.

1871, June 9 Line-displacements due to solar rotation detected by Vogel.

1871, Dec. 12 Total eclipse visible in India. Janssen observes reflected Fraunhofer lines in spectrum of corona.

1872 Conclusion of a three years' series of observations on lunar heat by Lord Rosse.

1872 Spectrum of Vega photographed by H. Draper.

1872 Faye's cyclonic hypothesis of sun-spots.

1872 Young's solar-spectroscopic observations at Mount Sherman.

1872 Cornu's experiments on the velocity of light.

1872, Nov. 27 Meteoric shower connected with Biela's comet.

1873 Determination of mean density of the earth by Cornu and Baille.

1873 Solar photographic work begun at Greenwich.

1873 Erection of 26-inch Washington refractor.

1874 Light-equation redetermined by Glasenapp.

1874 Vogel's cla.s.sification of stellar spectra.

1874, Dec. 8 Transit of Venus.

1876 Publication of Neison's _The Moon_.

1876, Nov. 24 New star in Cygnus discovered by Schmidt.

1876 Spectrum of Vega photographed by Huggins. First use of dry gelatine plates in celestial photography.

1877, May 19 Klein observes a supposed new lunar crater (Hyginus N.).

1877 Measurement by Vogel of selective absorption in solar atmosphere.

1877, Aug. 16-17 Discovery of two satellites of Mars by Hall at Washington.

1877, Sept. 23 Death of Leverrier.

1877 Ca.n.a.ls of Mars discovered by Schiaparelli.

1877 Opposition of Mars observed by Gill at Ascension.

Solar parallax deduced = 8.78".

1878, January Stationary meteor-radiants described by Denning.

1878 Publication of Schmidt's _Charte der Gebirge des Mondes_.

1878 First observations of Great Red Spot on Jupiter.

1878 Conclusion of Newcomb's researches on the lunar theory.

1878, May 6 Transit of Mercury.

1878 Foundation of Selenographical Society.

1878, July 29 Total eclipse visible in America. Vast equatoreal extension of the corona.

1878, October Completion of Potsdam Astrophysical Observatory.

1878, Dec. 12 Lockyer's theory of celestial dissociation communicated to the Royal 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 ma.s.s-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 Tebb.u.t.t's comet.

1881, June 24 Its spectrum photographed by Huggins.

1881, June Photographs of Tebb.u.t.t'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 = 879".

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.