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
 
 
CHAPTER XXII.
 
Evaporation—Distribution of Vapour—Dew—Hoar-Frost—Fog—Region of Clouds—Forms of Clouds—Rain—Distribution of Rain—Quantity—Number of rainy Days in different Latitudes—Rainless Districts—Snow Crystals—Line of perpetual Snow—Limit of Winter Snow on the Plains—Sleet—Hail—Minuteness of the ultimate Particles of Matter—Their Densities and Forms—Their Action on Light—Colour of Bodies—Colour of the Atmosphere—Its Absorption and Reflection of Light—Mirage—Fog Images—Coronæ and Halos—The Rainbow—Iris in Dewdrops—The Polarization of the Atmosphere—Atmospheric Electricity—Its Variations—Electricity of Fogs and Rain—Inductive Action of the Earth—Lightning—Thunder—Distribution of Thunder-Storms—Back Stroke—St. Elmo’s Fire—Phosphorescence—Aurora—Magnetism—Terrestrial Magnetism—The Dip—Magnetic Poles and Equator—Magnetic Intensity—Dynamic Equator—Declination—Magnetic Meridian—Lines of equal Variation—Horary Variations—Line of Alternate Horary Phenomena—Magnetic Storms—Coincidence of the Lines of equal Magnetic Intensity with Mountain Chains—Diamagnetism 272
 
 
CHAPTER XXIII.
 
Vegetation—Nourishment and Growth of Plants—Effects of the different Rays of the Solar Spectrum—Classes—Botanical Districts 298
 
 
CHAPTER XXIV.
 
Vegetation of the Great Continent—Of the Arctic Islands—And of the Arctic and North Temperate Regions of Europe and Asia 312
 
 
CHAPTER XXV.
 
Flora of Tropical Asia—Of the Indian Archipelago, India, and Arabia 323
 
 
CHAPTER XXVI.
 
African Flora—Flora of Australia, New Zealand, Norfolk Island, and of Polynesia 330
 
 
CHAPTER XXVII.
 
American Vegetation—Flora of North, Central, and South America—Antarctic Flora—Origin and Distribution of the Cerealia—Ages of Trees—Marine Vegetation 341
 
 
CHAPTER XXVIII.
 
Distribution of Insects 363
 
 
CHAPTER XXIX.
 
Distribution of Marine Animals in general—Fishes—The Marine Mammalia—Phocæ, Dolphins, and Whales 368
 
 
CHAPTER XXX.
 
Distribution of Reptiles—Frogs and Toads—Snakes, Saurians, and Tortoises 383
 
 
CHAPTER XXXI.
 
Distribution of Birds in the Arctic Regions—In Europe, Asia, Africa, America, and the Antarctic Regions 392
 
 
CHAPTER XXXII.
 
Distribution of Mammalia throughout the Earth 412
 
 
CHAPTER XXXIII.
 
The Distribution, Condition, and future Prospects of the Human Race 436
 
 
APPENDIX.
 
Table of Heights above the Sea of some of the Principal Mountain Chains 475
 
Glossary 487
 
Index 527
PHYSICAL GEOGRAPHY.