Part 20 (1/2)

[Footnote 441: _Proc. Roy. Society_, vol. xvi., p. 29.]

[Footnote 442: _Recherches sur le Spectre Solaire_, p. 38.]

[Footnote 443: _Am. Jour. of Science_, 1881, vol. xxi., p. 41. Hastings stipulated only for some member of the triad, carbon, silicon, and boron.]

[Footnote 444: Ranyard, _Knowledge_, vol. xvi., p. 190.]

[Footnote 445: Young, _The Sun_, p. 337, ed. 1897.]

[Footnote 446: H. Draper, _Quart. Journ. of Sc._, vol. i., p. 381; also _Phil. Mag._, vol. xvii., 1840, p. 222.]

[Footnote 447: Reproduced in Arago's _Popular Astronomy_, plate xii., vol. 1.]

[Footnote 448: _Report Brit. a.s.s._, 1859, p. 148.]

[Footnote 449: _Phil. Trans._, vol. clii., p. 407.]

[Footnote 450: _Researches in Solar Physics_, part i., p. 20.]

[Footnote 451: Both the phrase and the method were suggested by Faye, who estimated the average depth of the luminous sheath of spots at 2,160 miles. _Comptes Rendus_, t. lxi., p. 1082; t. xcvi., p. 356.]

[Footnote 452: _Month. Not._, vol. lv., p. 74.]

[Footnote 453: Sidgreaves, _Ibid._, p. 282; Cortie, _Ibid._, vol.

lviii., p. 91.]

[Footnote 454: Explained by East as refraction-effects. _Jour. Brit.

Astr. a.s.s._, vol. viii., p. 187.]

[Footnote 455: _Proc. Roy. Soc._, vol. xiv., p. 39.]

[Footnote 456: _Potsdam Publicationen_, No. 18; _Astr. Nach._, Nos.

3,000, 3,287.]

[Footnote 457: Faye, _Comptes Rendus_, t. cxi., p. 77; Belopolsky, _Astr. Nach._, No. 2,991.]

[Footnote 458: _Ibid._, Nos. 3,275, 3,344.]

[Footnote 459: Lockyer, _Contributions to Solar Physics_, p. 70.]

[Footnote 460: _Le Soleil_, p. 87.]

[Footnote 461: _Proc. Roy. Soc._, vol. xv., p. 256.]

[Footnote 462: _Phil. Mag._, vol. xvi., p. 460.]

[Footnote 463: _Recherches sur la Rotation du Soleil_, p. 12.]

[Footnote 464: Hale, _Astr. and Astrophysics_, vol. xi., p. 814.]