Section I. How We Ought to Think Upon What We Know 314

II. Ever Part of the Earth a Home for something 316 III. Birds of Passage, Dormice, and Snails 318 IV. The Rein-deer--the Camel 322 V. Benefit of the difference of Climate 324 VI. The same Organs in different Animals developed in various modes and degrees--the Acalepha, Actinia, and Sepia 326 VII. How the Stars and we are connected together-- Gravitation--Aerolites 330 VIII. Dew 332 IX. How every thing is endowed with a tendency to preserve its own life, and the existence of its race 334 X. The Bud of the Poppy--long retention of life by seeds and roots 336 XI. Of Seeds which are furnished with wings or sails 339 XII. Conclusion of the conclusion 340

List of Plates.

PLATE Page

I. EXTINCT ANIMALS THAT ONCE LIVED WHERE DORSETSHIRE NOW IS 5

II. EXTINCT ANIMALS THAT ONCE LIVED WHERE PARIS NOW IS 21

III. GREAT BONE CAVERN OF GAYLENREUTH 30

IV. GIGANTIC ELK AND MEGATHERIUM 38

V. VESUVIUS, WITH THE PINE-TREE CLOUD 64

VI. VESUVIUS IN ERUPTION AT NIGHT 66

VII. THE GEYSERS OF ICELAND 78

VIII. ISLAND OF STAFFA 93

IX. FINGAL'S CAVE 97

X. FORUM OF POMPEII 131

XI. GREAT FALL OF NIAGARA 135

XII. ESCAPE ON THE ICE 157

XIII. THE WATER-SPOUT 194

XIV. ACTINIÆ--CORAL BUILDERS 206

XV. SEPIAS 231

XVI. NAUTILUS 239

XVII. AURORA BOREALIS (FRONTISPIECE.)

XVIII. SPECTRE OF THE BROCKEN 285

XIX. DOVER CASTLE 293

XX. FATA MORGANA 299

WONDERS OF THE EARTH,

SEA, AND SKY.