vi CONTENTS. 



PAGE 



CiiAPTEK XII.— Thcor}' of Whewell on the Origin and Propagation of Tidal "Waves. 

 — Origin of the 'lide in each Oceanic Basin. — "Establishment" of Ports. — 

 " Cotidal " Lines 101 



CHArTER XIII. — Apparent Irregularities of the Tides. — Extraordinary size of the 

 Tidal Wave in certain Bays. — Interference of Ebb and Flow. — Diurnal Tides. 

 — Inequalities of Successive Tides 106 



Chapter XIV.— Tidal Cuncnts. — Races and Whirlpools. — Tidal Eddies.— River 



Tides 117 



Chapter XV. — Ebb and Flow in Lakes and Inland Seas.— Currents of the Euripus. 



— Scylla and Charybdis 124 



BOOK IV. -THE SHORES AND ISLANDS. 



Chapter XVI. — Incessant Modifications of the Coast-line. — The Fjords of Scan- 

 dinavia and other Countries near the Poles 130 



Chapter XVII. — Filling up of the Fjords by Marine and Fluvial Alluvium . . 137 



Chapter XVIII.— Destruction of Cliffs.- The Coasts of the Channel.— The Straits 

 of Dover. — Action of Shingle and Sand. — Giants' Cauldrons. — Spouting "Wells 

 on the Coasts.— Tidal Wells 144 



Chapter XIX. — Undermining of Rocks. — Varied aspect of Cliffs. — Platforms at 

 their Bases. — Resistance of the Coasts. — Breakwaters formed by the Rubbish. — 

 Heligoland. — Destruction of Low Shores .... ... 153 



Chapter XX. — Normal Form of Shores. — Curves of " Greatest Stability." — Form- 

 ation of New Shores. — Coast Ridges and Sand-banks. — Inland Bays . . 163 



Chapter XXI. — Shallows of the Coast. — Deposit from Calcareous Rocks. — Appear- 

 ance of Strands and Beaches . . . 181 



Chapter XXII. — Origin of Islands. — Islands of Continental Origin. — Rocks of the 

 Shores. — Islands of Depression, Elevation, and Erosion. — Islands of Oceanic 

 Origin.— Atolls and Volcanos 189 



BOOK v.— THE DUNES. 



Chapter XXIII. — Dunes resulting from the decomposition of Rocks. — Formation 



of Moving Dunes on the Sea-shore. — Symmetrical disposition of Ridges of Sand 198 



Chapter XXIV. — Height of the Hillocks. — Advance of the Dunes. — Displacement 



of'Etangs." — Disappearance of Villages 207 



Chapter XXV.— Obstacles opposed by Nature to theProgi-ess of Dunes.— Fixation 



of the Sands by Seeds 215 



PAET II.— THE ATMOSPHEEE AND METEOEOLOGY. 



BOOK I.— THE AIR AND WINDS 



Chapter I. — Air the Agent of the Vital Circulation of the Planet. — Phenomena of 



Reflection and Refraction. — Mirage ........ 220 



