454 



Light, interference of, 161, 187. 



, diffraction of. 168. Notes 193, 



196, 197. 



of sun and moon, 239. 



of comets, 357. 



of fixed stars, 362. 



action of, on retina, 172. 



electric, 279. 



l>olarizalion of, 173. 



emanating theory of, 161. 



undulatory theory of, 162 etseq. 



objections to the undulatory 



theory of, removed, 190. 



, length and frequency of the 



undulations of, 161. 



Lightning and its effects, 282. 



, its velocity, 284. 



Lines of the second order, or conic 

 sections, 5. Note 22. 



of no variation, 301. 



of perpetual snow, 256. 



, isothermal, 259. 



, isogeothermal, 252. 



Longitude, terrestrial, 6, 30, 41. 

 Notes 11, 95. 



, celestial, 9. Note 47. 



of perihelion, 10. 



of nodes, 10. 



of epoch, 10. 



Lunar theory, 33. 



inequalities, 34. 



eclipses, 39. 



distance, 42. 



spheroid, 64. 



Lunar orbit, 33. 



, eccentricity and inclination of, 

 constant, 35. 



, nutation of, 39. 



Lyell, Mr., on the temperature of the 

 northern hemisphere, 70. His es- 

 timate of the number of volcanic 

 eruptions, 246. 



M. 



Mackintosh, Sir James, a quotation 

 from his "General View of the Pro- 

 gress of Ethical Philosophy," 1; 



Magnets, 305. ' 



, temporary, 317 et seq. 



Magnetic meridian, 301. 



polarity of the earth, 301. 



dip and equator, 301. 



poles, 300. 



intensity of the earth, 302. 



induction, 306. 



force, 308. 



fluid, 308. 



and electric forces, 310. 



Magnetism in general, 305. 



of different substances, 305. 



and electricity identical, 3-23. 



of the sun and planets, 334. 



, terrestrial, 300, 330. 



Magneto-electricity, 322. 



Major axis of an ellipse. Note 23. 



of an orbit, 8. Note 42. 



, secular motion of, 17. 



of planetary orbits invariable 



in length, 19. 



Malus, M., his discovery of the po- 

 larization of light, 189. 



Mankind identical in species, 270. 



Marcet, M., on the tempuralure of 

 an Artesian well, 244. 



Marco Polo finds a difficulty of kin- 

 dling fire at great heighls, 114. 



Marine plants, their distribution, 

 267. 



Mariner's compass, 304. 



, variation of, 301. 



Mars eclipsed Jupiter, 41 



, parallax of, 53. 



, compression of, 57. 



, climate of, 239. 



Mass, 6. Note 27. 



of the sun and planets, 55. 



of Jupiter's satellites, 55. 



of the moon, 55. 



of Jupiter and the Jovial sys- 

 tem, 55. 



of comets, 352. 



Mathematical and Mechanical Sci- 

 ences, 2. Note 2. 



Matter, proportion of, in any two 

 planets, 55. Note 133. 



, the ultimate particles of, 96 et 



seq. 



, the attraction of, 4. Note 5. 



, its diffusion in space, 381. 



Maximum squares, 59. Note 136. 



point of heat in solar spectrum, 



214. 



Mayer, M., his catalogue of stars, 

 367. 



Mean time, 78. 



distance, 8. Note 41. 



motion, 9. Notes 43, 45. 



longitude, 9. Note 47. 



motions and major axes, their 



constancy, 19. 



motions of Jupiter and Saturn, 



law of, 24. 



motions of Venus and the earth, 



25. 



motions of Jupiler's satellites, 



law of, 27. 



Measures, standard? of, 84. 



