CONTENTS. 



CHAPTER L 



RECENT ADDITIONS TO OUR KNOWLEDGE OF THE 

 PLANETARY SYSTEM. 



SECTION I. 



PAOB 



THE DISCOVERT OP THE PLANET NEPTUNE, 9 



Irregularities in the motion of Uranus, . 10 



Labors of Mr. Adams, 15 



Researches of M. Le Verrier, 16 



Discovery of the Planet by Dr. Galle 22 



Search for old observations, 25 



True orbit of the Planet, 30 



Name given to the Planet, 31 



Is Neptune surrounded by a ring ? 36 



Discovery of a Satellite, 38 



Will Neptune account for the anomalies of Uranus ? ... 40 



Is Neptune the Planet predicted by Le Terrier ? . 42 



Why was not the Planet sooner discovered ? 50 



SECTION H. 



ZONE OF PLANETS BETWEEN MAES AND JUPITER, .... 54 



Discovery of thirty-sir new Asteroids, 63 



Elements of the Asteroids, 83 



Are they all fragments of a single body ? 86 



Relation of the Asteroids to each other, 90 



SECTION in. 

 DISCOVERY OF AN EIGHTH SATELLITE OF SATURN, .... 96 



SECTION IV. 

 OF THE SATELLITES OF URANUS, .... . 100 



SECTION Y. 

 DISCOVERY OF A NEW RING TO SATURN, 108 



