[16] R. S. Phil. Trans., vol. lxxiii., p. 484.
[17] Astr. Nach., No. 2,947.
[18] R. S. E. Trans., vol. xxvii. In 1901 Dr. Anderson discovered Nova Persei.
[19] Astr. Nach., No. 3,079.
[20] For a different explanation see Sir W. Huggins’s lecture, Royal Institution, May 13th, 1892.
[21] For the early history of the proposals for photographic cataloguing of stars, see the Cape Photographic Durchmusterung, 3 vols. (Ann. of the Cape Observatory, vols. in., iv., and v., Introduction.)
[22] R. S. Phil. Trans., 1850, p. 499 et seq.
[23] Ibid, vol. cliv., p. 437.
[24] Brit. Assoc. Rep., 1868, p. 165.