CHAPTER I.
INTRODUCTORY
Natural Advantages of the Territory of the Roman Empire—Physical Decay of that Territory—Causes of the Decay—Reaction of Man on Nature—Observation of Nature—Uncertainty of Our Historical Knowledge of Ancient Climates—Uncertainty of Modern Meteorology—Stability of Nature—Formation of Bogs—Natural Conditions Favorable to Geographical Change—Destructiveness of Man—Human and Brute Action Compared—Limits of Human Power—Importance of Physical Conservation and Restoration—Uncertainty as to Effects of Human Action
CHAPTER II.
TRANSFER, MODIFICATION, AND EXTIRPATION OF VEGETABLE AND OF ANIMAL SPECIES.
Modern Geography takes Account of Organic Life—Geographical Importance
of Plants—Origin of Domestic Vegetables—Transfer of Vegetable
Life—Objects of Modern Commerce—Foreign Plants, how
Introduced—Vegetable Power of Accommodation—Agricultural Products of
the United States—Useful American Plants Grown in Europe—Extirpation
of Vegetables—Animal Life as a Geological and Geographical
Agency—Origin and Transfer of Domestic Quadrupeds—Extirpation of Wild
Quadrupeds—Large Marine Animals Relatively Unimportant in
Geography—Introduction and Breeding of Fish—Destruction of
Fish—Geographical Importance of Birds—Introduction of
Birds—Destruction of Birds—Utility and Destruction of
Reptiles—Utility of Insects and Worms—Injury to the Forest by
Insects—Introduction of Insects—Destruction of Insects—Minute
Organisms
CHAPTER III.
THE WOODS.
The Habitable Earth Originally Wooded—General Meteorological Influence
of the Forest—Electrical Action of Trees—Chemical Influence of
Woods—Trees as Protection against Malaria—Trees as Shelter to Ground
to the Leeward—Influence of the Forest as Inorganic on
Temperature—Thermometrical Action of Trees as Organic—Total Influence
of the Forest on Temperature—Influence of Forests as Inorganic on
Humidity of Air and Earth—Influence as Organic—Balance of Conflicting
Influences—Influence of Woods on Precipitation—Total Climatic Action
of the Forest—Influence of the Forest on Humidity of Soil—The Forest
in Winter—Summer Rain, Importance of—Influence of the Forest on the
Flow of Springs—Influence of the Forest on Inundations and
Torrents—Destructive Action of Torrents—Floods of the
Ardeche—Excavation by Torrents—Extinction of Torrents—Crushing Force
of Torrents—Transporting Power of Water—The Po and its
Deposits—Mountain Slides—Forest as Protection against
Avalanches—Minor Uses of the Forest—Small Forest Plants and Vitality
of Seeds—Locusts do not Breed in Forests—General Functions of
Forest—General Consequences of Destruction of—Due Proportion of
Woodland—Proportion of Woodland in European Countries—Forests of Great
Britain—Forests of France—Forests of Italy—Forests of
Germany—Forests of United States—American Forest Trees—European and
American Forest Trees Compared—The Forest does not furnish Food for
Man—First Removal of the Forest—Principal Causes of Destruction of
Forest—Destruction and Protection of Forests by Governments—Royal
Forests and Game-laws—Effects of the French Revolution—Increased
Demand for Lumber—Effects of Burning Forest—Floating of
Timber—Restoration of the Forest—Economy of the Forest—Forest
Legislation—Plantation of Forests In America—Financial Results of
Forest Plantations—Instability of American Life