INDEX TO VOL. III. 



ACHROMATIC telescopes, 63. 



Adalbert, Prince, of Prussia, his observa- 

 tions on the undulation of the stars, 59. 



Alcor, a star of the constellation Ursa Ma- 

 jor, employed by the Persians as a test 

 of vision, 49, 50, 200. 



Alcyone, one of the Pleiades, imagined 

 the center of gravity of the solar sys- 

 tem by Madler, 198. 



Alphonsine Tables, date of their construc- 

 tion, 151. 



Anaxagoras of Clazomense, his theory 

 of the world-arranging intelligence, 11 ; 

 origin of the modern theories of rota- 

 tory motion, 12. 



Andromeda's girdle, nebula in, 142. 



Arago, M., letters and communications of, 

 to M. Humboldt, 46, 49, 67, 68, 73, 96, 

 207-209 ; on the effect of telescopes on 

 the visibility of the stars, 69 ; on the 

 velocity of light, 80, 84 ; on photometry, 

 92, 90 ; his cyanometer, 97. 



Aratus, a fragment of the work of Hip- 

 parchas preserved in, 109. 



Archimedes, his " Arenarius," 30. 



Avcturus, true diameter of, 89. 



Argulander, his view of the number of 

 the fixed stars, 105, 106 ; his additions 

 to Bessel's Catalogue, 115 ; on period- 

 ically variable stars, 166. 



ij Argus, changes in color and brilliancy 

 of, 135, 178, 179. 



Aristotle, his distinct apprehension of the 

 unity of nature, 13-15; his defective 

 solution of the problem, 15; doubts the 

 infinity of space, 29, 30 ; his idea of the 

 generation of heat by the movement of 

 the spheres, 124. 



aosy, the domain of the fixed stars, 



Astronomy, the observation of groups of 

 fixed stars, the first step in, 118 ; very 

 bright single stars, the first named, 89. 



Atmosphere, limits of the, 40, 41 ; effects 

 of an untransparent, 104. 



Augustine, St., cosmical views of, 124. 



Autolycus of Pitane, era of, 89, 90. 



Auzout's object-glasses, 62. 



Bacon, Lord, the earliest views on the ve- 

 locity of light found in his "Novum 

 Organum," 79. 



Baily , Francis, his revision of De Lalande's 

 Catalogue, 115. 



Bayer's lettering of the stars of any con- 

 stellation not an evidence of their rel- 

 ative brightness, 98. 



Berard, Captain, on the change of color 

 of the star y Crucis, 135. 



Berlin Academy, star maps of the, 11B. 



Bessel, on repulsive force, 34, 35 ; his star 

 maps have been the principal means of 

 the recognition of seven new planets, 

 116 ; calculation of the orbits of double 

 stars by, 211. 



Binary stars, 199. 



Blue stars, 136 ; less frequent than red, 209. 



Blue and green suns, the probable cause 

 of their color, 208. 



Bond, of the Cambridge Observatory, 

 United States, his resolution of the neb- 

 ula in Andromeda's girdle into small 

 stars, 142. 



Brewster, Sir David, on the dark lines of 

 the prismatic spectra, 44. 



British Association, their edition of La- 

 lande's Catalogue, 115. 



Bruno, Giordano, his cosmical views, 17 ; 

 his martyrdom, 17. 



Busch, Dr., his estimate of the velocity of 

 light incorrect, 82. 



Catalogues, astronomical, their great im- 

 portance, 113, 114 ; future discoveries 

 of planetary bodies mainly dependent 

 on their completeness, 114 ; list of, 114, 

 115 ; Halley's, Flamstead's, and others, 

 114 ; Lalande's, Harding's, Bessel's, 115 



Catasterisma of Eratosthenes, 89, 90. 



a Centauri, Piazzi Smyth on, 146, 147, 185; 

 the nearest of the fixed stars that have 

 yet been measured, 191, 192. 



Central body for the whole sidereal heav- 

 ens, existence of, doubtful, 197. 



Chinese record of extraordinary stars (of 

 Ma-tuan-lin), 109, 155-159; deserving of 

 confidence, 162. 



Clusters of stars, or stellar swarms, 140 ; 

 list of the principal, 141-143. 



Coal-sacks, a portion of the Milky Way in 

 the southern hemisphere so called, 137. 



Colored rings afford a direct measure of 

 the intensity of light, 96. 



Colored stars, 130; evidence of change 

 of color in some, 131, 132; Sir John 

 Herschel's hypothesis, 131 ; difference 

 of color usually accompanied by differ 

 ence of brightness, 209. 



Comets, information regarding celestial 

 space, derived from observation on, 31, 

 39 ; number of visible ones, 151. 



Concentric rings of stars, a view favored 

 by recent observation, 149. 



Constellations, arrangement of stars into, 

 very gradual, 119. 



Contrasted colors of double stars, 207. 



Cosmical contemplation, extension of, la 

 the Middle Ages, 16. 



