TABLE OF CONTENTS.
INTRODUCTORY.
Natural Advantages of the Territory of the Roman Empire—Physical Decay of that Territory and of other parts of the Old World—Causes of the Decay—New School of Geographers—Reaction of Man upon Nature—Observation of Nature—Cosmical and Geological Influences—Geographical Influence of Man—Uncertainty of our Meteorological Knowledge—Mechanical Effects produced by Man on the surface of the Earth—Importance and Possibility of Physical Restoration—Stability of Nature—Restoration of Disturbed Harmonies—Destructiveness of Man—Physical Improvement—Human and Brute Action Compared—Forms and Formations most liable to Physical Degradation—Physical Decay of New Countries—Corrupt Influence of Private Corporations, Note, [1]
TRANSFER, MODIFICATION, AND EXTIRPATION OF VEGETABLE AND OF ANIMAL SPECIES.
Modern Geography embraces Organic Life—Transfer of Vegetable Life—Foreign Plants grown in the United States—American Plants grown in Europe—Modes of Introduction of Foreign Plants—Vegetables, how affected by transfer to Foreign Soils—Extirpation of Vegetables—Origin of Domestic Plants—Organic Life as a Geological and Geographical Agency—Origin and Transfer of Domestic Animals—Extirpation of Animals—Numbers of Birds in the United States—Birds as Sowers and Consumers of Seeds, and as Destroyers of Insects—Diminution and Extirpation of Birds—Introduction of Birds—Utility of Insects and Worms—Introduction of Insects—Destruction of Insects—Reptiles—Destruction of Fish—Introduction and Breeding of Fish—Extirpation of Aquatic Animals—Minute Organisms, [57]
THE WOODS.
The Habitable Earth originally Wooded—The Forest does not furnish Food for Man—First Removal of the Woods—Effects of Fire on Forest Soil—Effects of the Destruction of the Forest—Electrical Influence of Trees—Chemical Influence of the Forest.
Influence of the Forest, considered as Inorganic Matter, on Temperature: a, Absorbing and Emitting Surface; b, Trees as Conductors of Heat; c, Trees in Summer and in Winter; d, Dead Products of Tree; e, Trees as a Shelter to Grounds to the leeward of them; f, Trees as a Protection against Malaria—The Forest, as Inorganic Matter, tends to mitigate extremes.
Trees as Organisms: Specific Temperature—Total Influence of the Forest on Temperature.
Influence of Forests on the Humidity of the Air and the Earth: a, as Inorganic Matter; b, as Organic—Wood Mosses and Fungi—Flow of Sap—Absorption and Exhalation of Moisture by Trees—Balance of Conflicting Influences—Influence of the Forest on Temperature and Precipitation—Influence of the Forest on the Humidity of the Soil—Its Influence on the Flow of Springs—General Consequences of the Destruction of the Woods—Literature and Condition of the Forest in different Countries—The Influence of the Forest on Inundations—Destructive Action of Torrents—The Po and its Deposits—Mountain Slides—Protection against the Fall of Rocks and Avalanches by Trees—Principal Causes of the Destruction of the Forest—American Forest Trees—Special Causes of the Destruction of European Woods—Royal Forests and Game Laws—Small Forest Plants, Vitality of Seeds—Utility of the Forest—The Forests of Europe—Forests of the United States and Canada—The Economy of the Forest—European and American Trees Compared—Sylviculture—Instability of American Life, [128]
THE WATERS.
Land artificially won from the Waters: a, Exclusion of the Sea by Diking; b, Draining of Lakes and Marshes; c, Geographical Influence of such Operations—Lowering of Lakes—Mountain Lakes—Climatic Effects of Draining Lakes and Marshes.
Geographical and Climatic Effects of Aqueducts, Reservoirs, and Canals—Surface and Underdraining, and their Climatic and Geographical Effects—Irrigation and its Climatic and Geographical Effects.
Inundations and Torrents: a, River Embankments; b, Floods of the Ardèche; c, Crushing Force of Torrents; d, Inundations of 1856 in France; e, Remedies against Inundations—Consequences if the Nile had been confined by Lateral Dikes.
Improvements in the Val di Chiana—Improvements in the Tuscan Maremme—Obstruction of River Mouths—Subterranean Waters—Artesian Wells—Artificial Springs—Economizing Precipitation, [330]
THE SANDS.
Origin of Sand—Sand now carried down to the Sea—The Sands of Egypt and the adjacent Desert—The Suez Canal—The Sands of Egypt—Coast Dunes and Sand Plains—Sand Banks—Dunes on Coast of America—Dunes of Western Europe—Formation of Dunes—Character of Dune Sand—Interior Structure of Dunes—Form of Dunes—Geological Importance of Dunes—Inland Dunes—Age, Character, and Permanence of Dunes—Use of Dunes as Barrier against the Sea—Encroachments of the Sea—The Lümfjord—Encroachments of the Sea—Drifting of Dune Sands—Dunes of Gascony—Dunes of Denmark—Dunes of Prussia—Artificial Formation of Dunes—Trees suitable for Dune Plantations—Extent of Dunes in Europe—Dune Vineyards of Cape Breton—Removal of Dunes—Inland Sand Plains—The Landes of Gascony—The Belgian Campine—Sands and Steppes of Eastern Europe—Advantages of Reclaiming Dunes—Government Works of Improvement, [451]
PROJECTED OR POSSIBLE GEOGRAPHICAL CHANGES BY MAN.
Cutting of Marine Isthmuses—The Suez Canal—Canal across Isthmus of Darien—Canals to the Dead Sea—Maritime Canals in Greece—Canal of Saros—Cape Cod Canal—Diversion of the Nile—Changes in the Caspian—Improvements in North American Hydrography—Diversion of the Rhine—Draining of the Zuiderzee—Waters of the Karst—Subterranean Waters of Greece—Soil below Rock—Covering Rocks with Earth—Wadies of Arabia Petræa—Incidental Effects of Human Action—Resistance to great Natural Forces—Effects of Mining—Espy's Theories—River Sediment—Nothing small in Nature, [517]