CONTENTS. 



INTRODUCTION . . .'," ' . ~ ' /. "7- " , . . Pag 1 



SECTION I. 



Attraction of a Sphere Form of Celestial'Bodies Terrestrial Gravitation 

 retains the Moon in her Orbit The Heavenly Bodies move in Conic 

 Sections Gravitation proportional to Mass Gravitation of the Particles 

 of Matter Figure of the Planets How it affects the Motions of their 

 ' Satellites Rotation and Translation impressed by the same Impulse- 

 Motion of the Sun and Solar System 4 



SECTION II. 



Elliptical Motion Mean and True Motion Equinoctial Ecliptic Equi- 

 noxes Mean and True Longitude Equation of Center Inclination of 

 the Orbits of Planets Celestial Latitude Nodes Elements of an Orbit 

 Undisturbed or Elliptical Orbits Great Inclination of the Orbits of 

 the new Planets Universal Gravitation the Cause of Perturbations in 

 the Motions of the Heavenly Bodies Problem of the Three Bodies 

 Stability of Solar System depends upon the Primitive Momentum of the 

 Bodies 8 



SECTION in. 



Perturbations, Periodic and Circular Disturbing Action equivalent to 

 three Partial Forces Tangential Force the Cause of the Periodic Ine- 

 qualities in Longitude, and Secular Inequalities in the Form and Position 

 of the Orbit in its own Plane Radial Force the Cause of Variations in 

 the Planet's Distance from the Sun It combines with the Tangential 

 Force to produce the Secular Variations in the Form and Position of the 

 Orbit in its own Plane Perpendicular Force the Cause of Periodic Per- 

 turbations in Latitude, and Secular Variations in the Position of the 

 Orbit with regard to the Plane of the Ecliptic Mean Motion and Major 

 Axis Invariable Stability of System Effects of a Resisting Medium 

 Invariable Plane of the Solar System and of the Universe Great Ine- 

 quality of Jupiter and Saturn 12 



SECTION IV. 



Theory of Jupiter's Satellites Effects of the Figure of Jupker upon his 

 Satellites Position of their Orbits Singular Laws among the Motions 

 of the first three Satellites Eclipses of the Satellites Velocity of Light 

 Aberration Ethereal Medium Satellites of Saturn and Uranns 26 



