Bøker av U S Coast and Geodetic Survey

In view of the growing interest in maps and charts as brought about by the interrelation of countries and communities, the purpose of this publication is to supply in outline form the underlying principles of constructive cartography. It is also intended to illustrate the development of the scientific system of today and the educational value of this branch of human activities. A knowledge of the horizontal and vertical location of places and the configuration of the earth's surface are essential factors in carrying on the major activities of a nation. Such information as relates to land surfaces is given on the modern topographic map; the submarine relief and the navigational routes of travel and commerce are supplied by the nautical chart, and, in a similar manner, the needs of air travel and air commerce are served by the aeronautical chart. A nation of vast resources and industrial developments can well afford to provide maps and charts for the extension of its highways, railroads, and airways in all directions; for the harnessing of its rivers to furnish water power and irrigation; and for providing means of protection against the overflow of river banks and the encroachments of the sea upon its beaches. In the interests of navigation the mariner requires charts that supply not only the necessary accuracy in delineation and facility for use, but charts that are in keeping with the development of a nation's ports, its commerce, and the ever changing natural conditions. It is the purpose of this book to trace briefly the attempts made through the ages to depict on paper accurate geographic information which will lead to a better understanding of the terrain and the sea, their history and relationship, their characteristics and phenomena. It will also outline what are now considered the best methods of securing and utilizing map data and to indicate how to use the maps and charts after they have been constructed and printed.