CONTENTS. 



XIX 



Aristotle ; Archimedes ; Euclid ; Ptolemy ; Alhazen j 

 Vitellio ; R. Bacon ; 473. Jansen ; Galileo ; Kepler; 

 Scheiner ; Rheita ; Maurolycus; DeDoniinis; Silel- 

 lius ; Descartes ; 474. Ferraat ; Leibnitz ; Barrow ; 

 Boyle ; Hooke ; 475. Newton ; Grimaldi ; 476- 

 Bartholin; Huygens; Roemcr , Bradley ; 477. Bou- 



PART THE THIRD 



Lecture xli. On the fixed stars; 

 487. 



Division of the subjects of physics ;487. Astronomy ; 

 488. Empty S|;ace ; fixed stars ; 489. Light of the 

 stars; Figure; Twinkling; Number; Magnitudes; 

 490. Distances of the stars ; 491. Clusters or ne- 

 bulae ; 492. Arrangement of the stars in general ; 

 Milky way ; Proper motions of the ^stars ; 493. Dr. 

 Herschel's division of stars and nebulae ; Changes of 

 the stars ; 494. Constellations ; 495. Representa- 

 tions of the stars ; AUineations ; 496 . .498. 



Lecture xLir. On the solar system ; 

 ^99- 



The sun a star; Progressive motion of the sun; 

 499. Orbit of the sun ; Rotation ; 500. Spots ; 

 Solar heat ; 501. Sun's attraction ; Solar atmosphere ; 

 502. Planets ; Ecliptics ; 503. Change of position 

 of the ecliptic ; Nodes ; Keplerian laws ; 504. Rota- 

 tion of the planets ; Precession of the equinoxes ; 505. 

 Nutation of the earth's axis ; Proportional distances 

 of the planets ; Mercury ; 506. Venus ; The earth ; 

 Mars; 507. Juno; Pallas; Ceres; Jupiter ; Saturn ; 

 608. Georgian planet ; Unknown planets; Satellites; 

 509. Moon ; 510. Satellites of Jupiter ; Ring of 

 Saturn ; 511. Comets ; 512. Number and orbits of 

 the comets; 513. 



Lecture xliii. On the laws of gra- 

 vitation ; 



Newton's great discovery ; Attraction of spherical 

 bodies; 515. Extent of tiie force ofgravity ; 5l6. 

 Sun's change of place ; Orbits of the planets ; Kep- 

 lerian laws ; 517. Universality of gravitation ; Mo- 

 tions of the apsides and nodes; Changes of the 

 •cliptic ; Forms of the planets ; 518. Precession ; 

 Nutation; Lunar motions; 519. Disturbing force of 

 the Run i 520. Acceleration of the moon's motion ; 



guer ; Porterfield ; Jurin ; Smith ; Doliond ; Hall . 

 478. Euler ; 479. Lambert ; Mathematical opti- 

 cians ; Mazeas; Dutour ; Comparetti ; Priestley; 

 480. Delaval ; R. Darwin ; Atmospherical refrac- 

 tion ; Wollaston; Ritter ; Herschcl ; 481. Laplace J 

 Attempts of the author ; 482. Chronological table ; 483' 



.. PHYSICS ; 485. 



Moon's rotation ; Orbits of comets; 521. Predictions 

 of Halley and Clairaut ; 522. Chronological table; 433. 



Lecture xliv. On the appear- 

 ances of the celestial bodies; 523. 



Apparent motions to be described after the real 

 ones; Motions of the stars and sun ; Motions of the 

 earth ; 523. Apparent revolution of the sun ; 524. 

 Sun's apparent diameter; Length of summer and win- 

 ter"; Day and night ; Sun's apparent path ; 525. Cen- 

 trifugal force ; Places of the stars ; Twilight , 526. 

 Relative positions and phases of the planets; 527. 

 Phases of the moon: Lunar eclipses ; 528. Eclipses 

 of the sun ; Series of eclipses ; 529. Harvest moon j 

 Eclipses of Jupiter's satellites ; 530. Comets; Light 

 of the heavenly bodies ; Planetary worlds ; 531. Fon- 

 tenelle ; Mercury ; Venus ; 532. Moon ; 533. Mars ; 

 Newly discovered planets ; Jupiter ; 534. Saturn ; 

 Georgian planet ; 535. 



Lecture xlv. On practical astro- 

 nomy ; 536. 



Real motions neglected ; Situation of a point in the 

 heavens ; Meridian ; 536. Astronomical instruments : 

 Time; Sidereal day; .Solar day; Equation of time' 

 537. Dialling; Chronology; 538. Calendar; 539. 

 Improvement suggested ; Republican calendar ; Me- 

 tonic cycle ; Golden number ; 540. Epact ; Moon's 

 age; Julian period; Astronomical time ; Quadrants; 

 Transit instruments ; 541. Iladley's quadrant ; De- 

 clinations ; Refraction and parallax ; 542. Latitudes: 

 Longitudes ; 543. Lunar observations ; Distance of 

 the sun ; Transits ; 544. Densities of the sun add 

 planets; Artificial globe ; " 565". Planispheres ;;566- 

 Orreries ; 567. 



Lecture xlvi. On Geography; 568. 



Particular account of the earth; Curvature of its 

 surface; Direction of the plumb line; 568. Ellipti- 



