clviii INDEX. 



Comets, p. 394 412, and cxli. cli. (Notes 645678). Vibratory motion of 

 effluxes of, p. xiii.(Note 83). Unite smallness of mass with the occupation of 

 vast space, p. 397. Chinese and Mexican accounts of, p. 398400. Biela's 

 comet seen to divide into two, p. 405 407 and v cxlvii. (Notes 669 and 670.) 

 Interior, p. 408 410. Table of interior, p. 410. Chronology of bright, p. 

 cxlii. and cxliii. cxlvi. (Notes 649 and 656.) 



Constellations, introduction of, p. 101 105 and liii. (Note 197.) The constella- 

 tion of the southern cross, and search after a southern pole star and southern 

 Wain, p. Ixxxiii. Ixxxiv. (Note 401.) 



Cyanometer, p. xxxix. 



Crystal sphere, see " Sphere," and p. liv. Ivi. (Notes 200 and 202.) 



Descartes, "Traite" du Monde," p. 1920. 

 Double stars, see " Stars." 



Earth, numerical data relating to the, as a planet, p. 351. Influence of the incli- 

 nation of its axis of rotation on climate, p. 327331. 



Ecliptic, increase or decrease of its obliquity restricted within narrow limits, 

 p. 330333 and cxxii. (Note 534.) 



Electricity, its relation with light, heat, and magnetism, p. 35289. 



Encke's comet, its period of revolution diminished by a resisting medium, 

 p. 4041 and xiii. (Note 83.) Description of, p. cxlvii. (Note 667.) 



Ether, see " ^Ether," and p. 3435, 36, 3941, xiii. xiv. (Notes 83 and 86.) 



Etymology of the terms signifying fixed stars, p. 28. Of epithets applied to an 

 .Ether, p. 3335 and x. Of names of stars, p. lx. Ixi. (Notes 218 and 219.) 

 Of names and terms applied to different planets and to the days of the week, 

 cvi. cxiv. (Notes 504510.) 



Eunomia, recent discovery and elements of, p. 456. 



Editor's note, terrestrial magnetism, p. 36. 



Fire-balls, p. 435438. 



Fluctuation of stars, p. 55-56 and xxii. xxiii. (Notes 113114, and 453.) 



Galaxy, see Milky Way. 



General remarks on the treatment of the Cosmos, p. 911. 

 Greeks, views of the Cosmos, or of Nature, by the different schools of philosophy 

 among the, p. 11 16. 



Irradiation, phenomena of, p. 358 and cxxix. (Notes 578 nd 579.) 

 Jupiter, p. 375 -378 and cxxxv. cxxxvi. Satellites of, see " Satellites." Belts, 

 p. 377378 and cxxxvi. (Note 617.) 



Kepler, his early views respecting attraction, his mathematical genius, &c. p. 18 

 19 and r. vi. His " laws," p. 450451 . 



Light proceeding from different sources, refractive properties, p. 55. Wollas 

 ton's lines, p. 45. Optical means of distinguishing direct from reflected 

 light, and their importance in physical astronomy, p. 46 47 and xvi xvii. 

 (Notes 98 -102), 283287 and cii. ciii. (Note 483.) Velocity of, and differences 

 of velocity according to the source of the, p. 46, 7277, xxx. and xxxiv. 

 (Notes 136146.) Experiments, Wheatstone, p. 46 and 7576 ; Fizeau, 7274 ; 

 Walker, 7677. Effect of a fainter, being placed by the side of a brighter, 



