CONTENTS. 



PAET I.— THE OCEAN. 



BOOK I.— THE SEAS. 



PAGE 



Chapter I. — General Considerations . . . 1 



Chapter II. — Oceanic Basins. — Depth of the Seas. — Level of the Surface of the 



Ocean 5 



Chapter III. — Composition of Sea- water. — Specific "Weight. — Salt Marshes, Natural 



and Artificial. — Various Substances. — Differences of Saltness. — Marine Salt . 22 



Chapter IV. — Various colours of Sea- water. — Eeflections, Transparency, and Proper 



Colour. — Temperature of the Depths of the Sea 29 



Chapter V. — Formation of Ice. — Ice-floes, Fields of Ice, and Icebergs. — Ice in the 



Baltic and the Black Sea 35 



Chapter VI. — "Waves of the Sea. — Regular and Irregular Undulations. — Height of 



the "Waves. — Their Size and Speed. — Ground-swell. — Coast- waves . . . 50 



BOOK '11.— CURRENTS. 



Chapter VII. — Great Movements of the Sea. — General Causes of Currents. — The 



Five Oceanic Rivers 60 



Chapter VIII.— The Gulf-stream.— Influence of this Current on Climate.— Its 



Importance to Commerce 64 



Chapter IX. — Currents of the South Atlantic and the Indian Ocean. — Double Eddy 



of the Pacific Ocean 78 



Chapter X. — Lateral Eddies. — Rennell's Current. — Counter-current in the Sea of 

 the Antilles. — Equilibrium of the Waters in the Baltic, the Bosphorus, at the 

 Entrances to the Mediterranean and the Red Sea. — Exchange of Water and Salt 

 between the Seas 85 



BOOK HI— THE TIDES. 

 Chapter XL— Oscillations of the Level of the Seas.— Theory of the Tides . . 92 



