514 



PHYSICAL SCIENCES. 



SABINE. 



SABINE, General, variations in the 

 magnetic elements investigated by, 

 343, 344. 



Sagittarius, comet traversing the 

 constellation of, 379 ; the Milky 

 Way in, 386 ; nebula, 414. 



Sahara, the, causing monsoons, 124. 



desert, extent, influence of, on 



the atmosphere, 243. 



Salt, Mr., papyrus sent from Egypt 

 by, 89. 



Sand, tubes in, formed by lightning. 

 293. 



Sandy deserts influencing temperature, 

 243. 



Sandwich Land, excess of cold in, over 

 corresponding latitudes, 241. 



Sargassa, or grassy sea, found in the 

 Atlantic, 253. 



Satellites, intensified action of attrac- 

 tion upon, 7 ; intimate union of, 

 with their primaries, 26 ; excep- 

 tions to a general law of the solar 

 system, 65, note ; rotations equal 

 to the times of their revolutions, 

 68 ; comet passing through, 69. 



, Jupiter's, proportion of their 



mass to that of their primary, 27 ; 

 disturbing force of attraction affect- 

 ing their orbits, 28 ; periodic and 

 secular inequalities, 28,29 ; eclipses, 

 30 ; rotation, 70 ; passage of a 

 comet through, 359 ; comet nearly 

 approaching, 370. 



of Saturn, 32 ; of Uranus and 



Neptune, 33. 



, mode of computing their masses, 



55 ; comparative density of, 58. 



of Neptune, 63. 



of the earth, shooting stars, 



423. 



Saturn, unequally occurring compen- 

 sations of disturbance in its motions, 

 15 ; disturbing influence of, on 

 Jupiter, exceutricity of its orbit 

 compared with Jupiter's, 17 ; re- 

 tarding the revolution of Jupiter's 

 nodes, 19 ; invariable plane passing 

 between Jupiter and, 24 ; observa- 

 tions on the mean motions of Ju- 

 piter and, 25, 26 ; eclipse of, 42 ; 

 internal structure, 58 ; astronomical 



SEA. 



tables of, 60 ; period of his year, 

 66 ; the rings of, described, 66-68 ; 

 his ring probably diamagnetic, 347 ; 

 action of, on Halley's comet, 362, 

 363 ; comets having their perihelia 

 in his orbit, 381. 



Saurian reptiles, distinct tribes of, 

 254. 



Saussure, M., temperature of mines 

 observed by, 228, 229 ; lichen dis- 

 covered by, 249. 



Savart, M., his researches and experi- 

 ments in acoustics, 132, 133 ; ex- 

 periments on vibrations of glass 

 rulers, 145-147 ; experiments show- 

 ing sympathetic undulations, 148, 

 149 ; discoveries on the nature of 

 voice, 152. 



Savary, M., orbital elements of a 

 double star determined by, 396 ; 

 his mode of ascertaining the actual 

 distances of fixed stars, 402, 

 403. 



Scheele, M., chemical changes effected 

 by the solar spectrum observed by, 

 203. 



Schroeter, height of planetary atmo- 

 spheres calculated by, 226. 



Schwabe, M., periodic variation in the 

 solar spots observed by, 344. 



Science, its value regarded as the 

 pursuit of truth, 1 ; errors of the 

 senses corrected by, 32 ; evidence 

 of its antiquity, 87. 



Sciences, mutual relations of forces 

 proving the connexion between, 

 319-321 ; analysis proving the 

 whole circle of, kin, 427, 428. 



Scoresby, Captain, phenomenon occa- 

 sioned by refraction observed by, 

 156. 



Scorpio, vacant patch of the Milky 

 Way in, 386 ; position of, 390 ; a 

 double star in, 395 ; nebula in, 

 414. 



Scotland, progress of the tidal wave 

 round, 94. 



Sea, the, inappreciable influence of, 

 on the direction of gravity, 77 ; 

 mean height of snow-line above the 

 level of, 241 ; comparative extent 

 of, 242. 



