visual observation of the Maia nebula with the
Pulkowa 30-inch refractor.
1886, March Photographs by the Henrys of the Pleiades, showing
2,326 stars with nebulae intermixed.
1886, May Photographic investigations of stellar parallax
undertaken by Pritchard.
1886, May 6 Periodical changes in spectra of sun-spots announced
by Lockyer.
1886, June 4 An international Photographic Congress proposed by Gill.
1886, Aug. 29 Total eclipse of the sun observed at Grenada.
1886, Oct. 1 Roberts's photograph showing annular structure of
the Andromeda nebula.
1886, Dec. 8 Roberts's photograph of the Pleiades nebulosities.
1886 Solar heat-spectrum extended by Langley to below
five microns.
1886, Dec. 28 Detection by Copeland of helium-ray in spectrum of
the Orion nebula.
1886 Thirty-inch refractor mounted at Nice.
1886 Publication of Argentine General Catalogue.
1886 Completion of Auwers's reduction of Bradley's
observations.
1886 Draper Memorial photographic work begun at
Harvard College.
1886 Photographic detection at Harvard College of bright
hydrogen lines in spectra of variables (Mira Ceti
and U Orionis).
1887, Jan. 18 Discovery by Thome at Cordoba of a great comet
belonging to the same group as the comet of 1882.
1887 Publication of Lockyer's _Chemistry of the Sun_.
1887, April 16 Meeting at Paris of the International Astrophotographic
Congress.
1887 Heliometric triangulation of the Pleiades by Elkin.
1887 L. Struve's investigation of the sun's motion, and
redetermination of the constant of precession.
1887 Von Konkoly's extension to 15 deg. S. Dec. of Vogel's
spectroscopic Catalogue.
1887 Auwers's investigation of the solar diameter.
1887 Publication of Schiaparelli's Measures of Double Stars
(1875-85).
1887, April 8 Death of Thollon at Nice.
1887, Aug. 19 Total eclipse of the sun. Shadow-path crossed Russia.
Observations marred by bad weather