F. Fallacies in judging of the bulk of objects by their apparent First meridian, what, 152, Fixed stars, why they appear of less magnitude when view- Their division into different classes and constellations, 380. G. General phenomena of a superior planet as seen from an in- Georgium Sidus, its distance, diameter, magnitude, annual Not readily distinguished from a fixed star, 63, n. Place of its nodes, 63, n. Its satellites, their distance, periods, and remarkable po- Gravity, demonstrable, 74-75. Keeps all bodies on the Earth to its surface, or brings Retains all the planets in their orbits, 75. Decreases as the square of the distance increases, 76. Demonstrated to be greater in the larger planets than in Hard to understand what it is, 113. Acts every moment, 115. Globe (Celestial), improved, 447. H. Harmony of the celestial motions, 78, None at the equator, 233. Remarkable at the polar circles, 241. In what years most and least advantageous, 245. Heat, decreases as the square of the distance from the Sun Why not greatest when the Earth is nearest the Sun, 151. Heavens, seem to turn round with different velocities as Only one hemisphere of them seen at once from any one Changes in them, 385. Horizon, what, 88, n. Horizontal Moon explained, 131. Horizontal parallax, of the Moon, 132; of the Sun, 135; Hour-circles, what, 153. Hour of time equal to 15 degrees of motion, 153. How divided by the Jews, Chaldeans, and Arabians, 395. I. Inclination of Venus's axis, 43. Of the Earth's, 49. Of the axis or orbit of a planet only relative, 145. Inhabitants of the Earth (or any other planet) stand on op- Julian period, 415. J. Jupiter, its distance, diameter, diurnal and annual revolu- The phenomena of its belts, 57. Has no difference of seasons, 58. Has four Moons, 58, their grand period, 58, the angles The inclination of its orbit, and place of its ascending The Sun's light 3000 times as strong on it as full Moon Is probably inhabited, 65. The amazing power required to put it in motion, 112. L. Light, the inconceivable smallness of its particles, 116; and 117. Its surprising velocity, 117, compared with the swiftness Decreases as the square of the distance from the lumi- Is refracted in passing through different mediums, 119, 120. Affords a proof of the Earth's annual motion, 139, 158. Limits of eclipses, 264. Line, of the nodes, what, 265; has a retrograde motion, 267. LONG, his glass sphere, 90. Longitude, how found, 152-155. Magellantic clouds, 385. M. Man, of a middle size, how much pressed by the weight of Matter, its properties, 74. Mean anomaly, what, 176. Mercury, its diameter, period, distance, &c. 40. Appears in all the shapes of the Moon, 40. When it will be seen on the Sun, 41. The inclination of its orbit and place of its ascending notle, 41. Its path delineated, 98. Experiment to shew its phases, and apparent motion, 102. Meridian, first, 152. Line, how to draw one, 166. Months, Jewish, Arabian, Egyptian, and Grecian, 391. Her phases, 51, 218. Shines not by her own light, 52. Has no atmosphere of any visible density, 52; nor seas, 53. How her inhabitants may be supposed to measure their Her light compared with day-light, 64. The eccentricity of her orbit, 73. Is nearer the earth now than she was formerly, 115. Her surface mountainous, 217: if smooth, she could give Why no hills appear round her edge, 217. Has no twilight, 218. Appears not always quite round when full, 219. Her phases agreeably represented by a globular stone Turns round her axis, 221. The length of her solar and sidereal day, 221. Her periodical and synodical revolution represented by 222. Her path delineated, and shewn to be always concave to Her motion alternately retarded and accelerated, 226. Earth at her conjunction, and why she does not then Rises nearer the time of sun-set when about the full in Moon continues above the horizon of the poles for fourteen Proved to be globular, 261; and to be less than the Earth, Her Nodes, 263; ascending and descending, 267; their Her acceleration proved from ancient eclipses, 278, n. Not invisible when she is totally eclipsed, and why, 314. ses, 318. How to find her age in any lunation by the Golden num- Morning and evening star, what, 104. Motion, naturally rectilineal, 74. Apparent, of the planets as seen by a spectator at rest on the outside of all their orbits, 94; and of the hea- Natural day, not completed in the time that the Earth turns New and full Moon, to calculate the times of, 318-328. New style, its origin, 390. Nodes of the planets' orbits, their places in the ecliptic, 38. Number of Direction, 412. 0. Objects, we often mistake their bulk by mistaking their dis- Appear bigger when seen through a fog than through Oblique sphere, what, 93. Olympiads, what, 279, n. Orbits of the planets not solid, 39. Orreries described, 430, 434, 437. |