rather than to the development of detail, and besides leaving large latitude to the teacher, the present volume aims to attain certain pedagogical ends. The pages are spread with cross references in the hope that the teacher may profit by our own practice of keeping constantly before the student what he has already studied in other connections. It is assumed that the student or reader who uses this book has at hand some standard atlas of physical, historical, and political maps, and that these maps are used as an essential part of the study. We strongly recommend also exercises involving map construction, map location, and the use of inexpensive outline maps for representation of data regarding topographic and climatic details, distribution of products, of industries, and of man. The triple authorship, corresponding practically to the three Parts of this book, expresses graphically our belief that the facts and principles involved in a study of the environmental relations of man require contributions from both the natural and the social sciences, and are best presented by a combination of workers from these two fields. Therefore while each author is directly responsible for the presentation of material from his particular field, the outline and general character of treatment is the joint work of the three authors. General editorial supervision has been exercised by the author of Part II. Thanks are due to Dr. Bowman and Dr. Huntington for suggestions and for corrections made upon the proofs. And we remember with gratitude and affection the helpful interest in our ideas and work displayed by the late Professor Edward G. Bourne. For permission to reproduce illustrations, in modified form, we express our sense of obligation to Professors Tarr and Dryer, the National Geographic Magazine, and the United States Geological Survey. The leading sources followed have been referred to here and there; but we have not sought to equip with full bibliographical apparatus a book which deals so largely with information easily accessible in unworked form. It is hardly necessary to say that we have made consistent use of the valuable publications of the several government departments, both of this country and of Canada-the Weather Bureau, Coast and Geodetic Survey, Geological Survey, Department of Commerce and Labor, Department of Agriculture, and so on. NEW HAVEN, CONNECTICUT THE AUTHORS VIII. ENVIRONMENTAL INFLUENCES: FLORA AND FAUNA, ETC. 12. RELIEF MAP OF THE LOWER COLORADO. 13. DISTRIBUTION OF POPULATION IN UTAH. 14. Length of Growing SeASON IN THE United States 23. PRODUCTION OF CORN IN THE UNITED STATES, 1850-1900 24. COTTON-PRODUCING AREAS of the United States. 257 267 25. PRODUCTION OF IRON ORE, PIG IRON, AND STEEL IN THE UNITED STATES, 1870-1906 298 26. DEVELOPMENT OF THE WORLD'S GOLD PRODUCTION SINCE 1493. PLATE I. MEDITERRANEAN COLONIZATION PLATE II. COLONIAL POSSESSIONS, SIXTEENTH TO NINETEENTH CENTURY GERMANY |