Part 63 (1/2)
[Footnote 1631: A. A. Common, _Memoirs R. Astr. Soc._, vol. i., p. 118.]
[Footnote 1632: Newcomb, _Pop. Astr._, p. 137.]
[Footnote 1633: _Month. Not._, vol. liv., p. 67.]
[Footnote 1634: Keeler, _Publ. Astr. Pac. Soc._, vol. ii., p. 160.]
[Footnote 1635: H. Grubb, _Trans. Roy. Dub. Soc._, vol. i. (new ser.), p. 2.]
[Footnote 1636: Hale, nevertheless (_Astroph. Jour._, vol. v., p. 128), considers that refractors preserve their superiority of visual light-grasp over Newtonian reflectors up to an aperture of 52-1/2, while equalisation is reached for the photographic rays at 34 inches.]
[Footnote 1637: _Astroph. Jour._, vol. v., p. 130.]
[Footnote 1638: _Phil. Trans._, vol. cxlviii., p. 465.]
[Footnote 1639: _Optics_, p. 107 (2nd ed., 1719).]
[Footnote 1640: _Observatory_, vol. viii., p. 85.]
[Footnote 1641: Holden on Celestial Photography, _Overland Monthly_, Nov., 1886.]
[Footnote 1642: _Observatory_, vol. xv., p. 283.]
[Footnote 1643: Bailey, _Astroph. Jour._, vol. x., p. 255.]
[Footnote 1644: _Harvard Circulars_, Nos. 2, 18, 24, 33;]
[Footnote 1645: Loewy, _Bull. Astr._, t. i., p. 286; _Nature_, vol.
xxix., p. 36.]
[Footnote 1646: _Nature_, vol. xxiv., p. 389.]
[Footnote 1647: _Ibid._, vol. xxix., p. 470.]
[Footnote 1648: _Trans. R. Dublin Soc._, vol. iii., p. 61.]
[Footnote 1649: _Observatory_, vol. vii., p. 167.]
[Footnote 1650: Loewy, _Bull. Astr._, t. i., p. 265.]
[Footnote 1651: _Phil. Trans._, vol. clxxi., p. 653.]
[Footnote 1652: Janssen, _L'Astronomie_, t. ii., p. 121.]
[Footnote 1653: Rev. A. L. Cortie, _Astr. and Astrophysics_, vol. xi., p. 400.]
[Footnote 1654: _Phil. Mag._, vol. xiii., 1882, p. 469.]
[Footnote 1655: _Bull. Astr._, t. iii., p. 331.]
APPENDIX
TABLE I
CHRONOLOGY, 1774-1893
1774, March 4 Herschel's first observation. Subject, the Orion Nebula.
1774 Sun-spots geometrically proved to be depressions by Wilson.
1774 First experimental determination of the earth's mean density by Maskelyne.
1781, March 13 Discovery of Ura.n.u.s.
1782 Herschel's first Catalogue of Double Stars.