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