[Footnote 622: Its non-atmospheric character was early defined by
Proctor, _Month. Not._, vol. xxxi., p. 196.]

[Footnote 623: _Astroph. Jour._, vol. vi., p. 412.]

[Footnote 624: _Ibid._, vol. xi., p. 165.]

[Footnote 625: _Ibid._, p. 243.]

[Footnote 626: _Sun's Place in Nature_, pp. 111, 288.]

[Footnote 627: _Abh. d. Koen. Boehm Ges. d. Wiss._, Bd. ii., 1841-42, p.
467.]

[Footnote 628: In a paper read before the Societe Philomathique de
Paris, December 23, 1848, and first published _in extenso_ in _Ann. de
Chim. et de Phys._, t. xix., p. 211 (1870). Hippolyte Fizeau died in
September, 1896.]

[Footnote 629: _Astr. Nach._, No. 1,772.]

[Footnote 630: _Ibid._, No. 1,864.]

[Footnote 631: A. Cornu, _Sur la Methode Doppler-Fizeau_, p. D. 23.]

[Footnote 632: _Am. Jour. of Sc._, vol. xii., p. 321.]

[Footnote 633: _Ibid._, vol. xiv., p. 140.]

[Footnote 634: _Bull. Astronom._, February, 1884, p. 77.]

[Footnote 635: _Comptes Rendus_, t. xci., p. 368.]

[Footnote 636: _Month. Not._, vol. xliv., p. 170.]

[Footnote 637: See _ante_, p. 147.]

[Footnote 638: _Recherches sur la Rotation du Soleil_, Upsal, 1891.]

[Footnote 639: Harzer, _Astr. Nach._, No. 3,026; Stratonoff, _Ibid._,
No. 3,344.]

[Footnote 640: _Publ. Astr. Pacific Soc._, vol. ii., p. 193.]

[Footnote 641: _Proc. Roy. Society_, vols. xvii., p. 415; xviii., p.
120.]

[Footnote 642: _Comptes Rendus_, t. cxii., p. 1421; t. cxiii., p. 310.]

[Footnote 643: At the sun's distance, one second of arc represents about
450 miles.]

[Footnote 644: _Amer. Jour. of Sc._, vol. ii., p. 468, 1871.]

[Footnote 645: _Month. Not._, vol. xxxii., p. 51.]

[Footnote 646: _Nature_, vol. xxiii., p. 281.]

[Footnote 647: _Comptes Rendus_, t. lxxxvii., p. 532.]

[Footnote 648: _Ibid._, t. xcvi., p. 359.]

[Footnote 649: A. Brester, _Theorie du Soleil_, p. 66.]

[Footnote 650: Such prominences as have been seen to grow by the spread
of incandescence are of the quiescent kind, and present no deceptive
appearance of violent motion.]

[Footnote 651: _Proc. Roy. Soc._, vol. xxviii., p. 157.]

[Footnote 652: "Evolution and the Spectroscope," _Pop. Science Monthly_,
January, 1873.]

[Footnote 653: _Proc. Roy. Soc._, vol. xxiv., p. 353. These are the H
and K of prominences. H. W. Vogel discovered in 1879 a hydrogen-line
nearly coincident with H (_Monatsb. Preuss. Ak._, February, 1879, p.
118).]

[Footnote 654: _Proc. Roy. Soc._, vol. xxviii., p. 444.]