INDEX. 



ABERDEEN. 



ABERDEEN, high water at, 94. 



Absorption, influence of, on tempe- 

 rature, 239 ; difference of sea and 

 land in power of, 242 ; gradually 

 decreasing, in transmission of ra- 

 diant heat, 259; of radiant heat, 

 varying with substances, 268 ; a 

 transfer of force, 275, 276. 



Acceleration of the moon's mean mo- 

 tion, 37, 38. 



Adams, Mr., perturbation in Uranus's 

 motion computed by, 22 ; discovery 

 of Neptune, 62. 



Aerolites, theory of, 420, 423. 



Africa, tidal wave passing, 94 ; mean 

 annual equatorial temperature in, 

 245 ; indigenous productions of, 

 249, 250. 



Air, comparative velocity of light in 

 water and, 202. See Atmosphere. 



Airey, Professor, periodic inequality 

 in the solar system worked out by, 

 26 ; phenomenon observed by, dur- 

 ing an eclipse, 41 ; mass of Jupiter 

 ascertained by, 55 ; experiments 

 ascertaining its density, 57 ; astro- 

 nomical tables improved by, 63 ; 

 discoveries in polarization of light, 

 192, 193. 



Aldebaran, an optically double star, 

 401. 



Aleutian Islands, the, vegetation of, 

 252. 



Alexandria, arc of the meridian mea- 

 sured between Sycne and, 49. 



Algae, districts of distinct species of, 

 252 ; banks of, in the Atlantic, 253. 



Algol, fluctuations in lustre of, 390, 

 391. 



Alhazen, effects of refraction observed 

 by, 155. 



Alkalies, resolved into metallic oxides, 

 307. 



Alpha Antaris, " Coal Sacks " between 

 . Centauri and, 386. 



ANALYSIS. 



Alpha Aquilse, an optically double star, 

 401. 



Centauri, the parallax of, 54 ; 



its rank, 384 ; the Milky Way near, 

 386 ; parallax, as determined by 

 Henderson and Maclear, 387 ; dis- 

 tance from the sun, 388 ; orbit and 

 mass of, 399, 400 ; colour, 401 ; 

 amount of light emitted by, 404 ; 

 rate of its proper motion, 404, 405 ; 

 globular nebulous cluster, 414. 



Crucis, zone of stars passing 



through, 385 ; zone between >j Ar- 

 gtis and, 390 ; nebulous cluster 

 round, 415, 



Lyras, the polar star of the 



northern hemisphere, 82 ; parallax 

 of, 388 ; distance from the sun, 

 389 ; an optically double star, 400 ; 

 amount of light emitted by, 404. 



Orionis, a variable star, 393, 394. 



Alum, experiments on the crystalliza- 

 tion of, 106, 107 ; heat transmitted 

 through, 261, 262. 



Amazons, the river of, distance from 

 its mouth where tides are per- 

 ceptible, 98 ; area occupied by fo- 

 rests on, 243. 



America, course of the tidal wave 

 along its coasts, 93, 94; mean annual 

 equatorial temperature in, 245 ; 

 separation of isothermal lines in 

 high latitudes, t'6. ; number of 

 known species of plants indigenous 

 in, 249 ; number of species of trees, 

 252 ; shooting stars over the conti- 

 nent of, 421. 



, South, area of country raised by 



an earthquake in, 234. 



Ampere, M., his discovery in elec- 

 tricity, 316 ; theory of magnetism, 

 317, 318; experiment testing his 

 theory, 319, 320. 



Analysis, boundless dominion of, 427, 

 428. 



