Chapter I: Preface: To the New Edition

SINCE the publication of the first edition of this work, the Author has been able to correct many inaccuracies that had crept into it, and to collect much new matter from works since published, which is embodied in the present edition, and has considerably added to its size. The recently-published Second Volume of Baron Humboldt’s invaluable “Cosmos,”[1] with Colonel Sabine’s learned notes, and sundry papers that have appeared in the scientific periodicals of Europe, America, and India, bearing on questions of Physical Geography, have yielded profitable information.

It was the Author’s wish, and her Publisher’s intention, that the present edition should be accompanied by a series of Maps to illustrate the more important questions of Physical Geography treated of in it; but Mr. A. Keith Johnston having announced the publication of a new edition of his “Physical Atlas” in a reduced size, at a low price,[2] the first two Nos. of which have already appeared, the project was relinquished, in the belief that Mr. A. K. Johnston’s smaller Atlas will furnish suitable illustrations to this work.

The reader will find this edition enriched with some of the results of the recent researches of Messrs. Campbell, Thomson, Strachey, and Dr. Hooker in the Himalaya, which tend largely to elucidate the Physical History of that gigantic chain. The book is also indebted to Mr. Pentland for some new matter, hitherto unpublished, on the countries of South America visited by him during his two public missions to Peru and Bolivia.

The absence of the Author from England during the printing of the following sheets has obliged her to have recourse to a friend conversant with her subject to revise the press; to him she begs to express her acknowledgments, as well as to Sir William Jackson Hooker, who very kindly undertook to correct the portion of this new edition connected with Geographical Botany and Vegetable Physiology—subjects respecting which he has so much contributed to extend our knowledge. Captain Beechey has been good enough to render similar service, in revising certain passages bearing upon Hydrography.

_May, 1849._

CONTENTS.

CHAPTER I.

Of Physical Geography—Position of the Earth in the Solar System— Distance from the Sun—Civil Year—Inclination of Terrestrial Orbit—Mass of the Sun—Distance of the Moon—Figure and Density of the Earth from the Motions of the Moon—Figure of the Earth from Arcs of the Meridian—From Oscillations of Pendulum—Local Disturbances—Mean Density of the Earth—Known Depth below its Surface—Outline of Geology PAGE 13

CHAPTER II.

Direction of the Forces that raised the Continents—Proportion of Land and Water—Size of the Continents and Islands—Outline of the Land—Extent of Coasts, and proportion they bear to the Areas of the Continents—Elevation of the Continents—Forms of Mountains— Forms of Rocks—Connection between Physical Geography of Countries and their Geological Structure—Contemporaneous Upheaval of parallel Mountain Chains—Parallelism of Mineral Veins or Fissures—Mr. Hopkins’s Theory of Fissures—Parallel Chains similar in Structure—Interruptions in Continents and Mountain Chains—Form of the Great Continent—The High Lands of the Great Continent—The Atlas, Spanish, French, and German Mountains—The Alps, Balkan, and Apennines—Glaciers—Geological Notice 37

CHAPTER III.

The High Lands of the Great Continent (_continued_)—The Caucasus— The Western Asiatic Table-Land and its Mountains 54

CHAPTER IV.

The High Lands of the Great Continent (_continued_)—The Oriental Table-Land and its Mountains 58

CHAPTER V.

Secondary Mountain Systems of the Great Continent—That of Scandinavia—Great Britain and Ireland—The Ural Mountains—The Great Northern Plain 69

CHAPTER VI.

The Southern Low Lands of the Great Continent, with their Secondary Table-Lands and Mountains 77

CHAPTER VII.

Africa—Table-Land—Cape of Good Hope and Eastern Coast—Western Coast—Abyssinia—Senegambia—Low Lands and Deserts 85

CHAPTER VIII.

American Continent—The Mountains of South America—The Andes—The Mountains of the Parima and Brazil 93

CHAPTER IX.

The Low Lands of South America—Desert of Patagonia—The Pampas of Buenos Ayres—The Silvas of the Amazons—The Llanos of the Orinoco and Venezuela—Geological Notice 105

CHAPTER X.

Central America—West Indian Islands—Geological Notice 114

CHAPTER XI.

North America—Table-Land and Mountains of Mexico—The Rocky Mountains—The Maritime Chain and Mountains of Russian America 119

CHAPTER XII.

North America (_continued_)—The Great Central Plains, or Valley of the Mississippi—The Alleghany Mountains—The Atlantic Slope—The Atlantic Plain—Geological Notice—The Mean Height of the Continents 123

CHAPTER XIII.

The Continent of Australia—Tasmania, or Van Diemen’s Land— Islands—Continental Islands—Pelasgic islands—New Zealand—New Guinea—Borneo—Atolls—Encircling Reefs—Coral Reefs—Barrier Reefs— Volcanic Islands—Areas of Subsidence and Elevation in the Bed of the Pacific—Active Volcanos—Earthquakes—Secular Changes in the Level of the Land 136

CHAPTER XIV.

Arctic Lands—Greenland—Spitzbergen—Iceland—Its Volcanic Phenomena and Geysers—Jan Mayen’s Land—New Siberian Islands—Antarctic Lands—Victoria Continent 159

CHAPTER XV.

Nature and Character of Mineral Veins—Metalliferous Deposits— Mines—Their Drainage and Ventilation—Their Depth—Diffusion of the Metals—Gold—Silver—Lead—British Mines—Quicksilver—Copper—Tin— Cornish Mines—Coal—Iron—Most abundant in the Temperate Zones, especially in the Northern—European and British Iron and Coal— American Iron and Coal—Arsenic and other Metals—Salt—Sulphur— Diffusion of the Gems 168

CHAPTER XVI.

The Ocean—Its Size, Colour, Pressure, and Saltness—Tides—Waves— their Height and Force—Currents—their Effect on Voyages— Temperature—The Stratum of Constant Temperature—Line of Maximum Temperature—North and South Polar Ice—Inland Seas 188

CHAPTER XVII.

Springs—Basins of the Ocean—Origin, Course, and Heads of Rivers— Hydraulic Systems of Europe—African Rivers—the Nile, Niger, &c. 209

CHAPTER XVIII.

Asiatic Rivers—Euphrates and Tigris—River Systems South of the Himalaya—Chinese Rivers—Siberian Rivers 224

CHAPTER XIX.

River Systems of North America—Rivers of Central America—Rivers of South America and of Australia 234

CHAPTER XX.

Lakes—Northern System of the Great Continent—Mountain System of the same—American Lakes 245

CHAPTER XXI.

Temperature of the earth—Temperature of the Air—Radiation—Foci of Maximum Cold—Thermal Equator—Its Temperature, mean and absolute— Isothermal Lines—Continental and Insular Climates—Extreme Climates—Stability of Climate—Decrease of Heat in Altitude—Line of Perpetual Snow—Density of the Atmosphere—The Barometer— Measurement of Heights—Variations in Density and their Causes— Horary Variations—Independent Effect of the dry and aqueous Atmospheres—Mean height of Barometer in different Latitudes— Depression in the Antarctic Ocean and in Eastern Siberia— Barometric Storms—Polar and Equatorial Currents of Air— Trade-Winds—Monsoons—Land and Sea Breezes—Gyration of the Winds in the Extra-Tropical Zones—Winds in Middle European Latitudes— Hurricanes—The Laws of their Motion—Their Effect on the Barometer—How to steer clear of them—The Storm-Wave— Storm-Currents—Arched Squalls—Tornadoes—Whirlwinds—Water Spouts 254