National Geographic : 1904 May
THE GEOGRAPHY OF ALASKA* ILLUSTRATED BY A NEW MAP BY ALFRED H. BROOKS AMONG the many maps of Alaska which have appeared during the last half century, none has attempted to depict any but the hori zontal relation. The accompanying illustration, therefore, marks a distinct advance in that it also expresses the vertical element or relief, by the use of I,coo-foot contours. The scale of 2,500,000 (about 40 miles to the inch) has been adopted to facilitate compari son with a map of the United States on the same scale, also published by the Geological Survey. The compilation begun three years ago was done under the direction of the late Mr R. U. Goode, chiefly by Mr E. C. Barnard. This map, representing as it does a graphic synopsis of all that is known of the geography of Alaska, has great value, even though future surveys must show error in many of its details; for the general facts of the relief and drain age are known to be correctly indicated, and as surveys of this northern region progress, it will be possible to make ad justments and changes in new editions. In the main, the map is based on the work of the Geological Survey parties during the years 1898-1903, but the shore features were furnished by the charts of the U. S. Coast and Geodetic Survey. That no material might be overlooked, all other Alaskan maps were consulted, including those of the Army, the Navy and Revenue Marine Service, and the Russian, British, and Canadian governments; and when exact carto graphic data was lacking, the compiler had recourse to such information as had been collected by the Geological Survey parties from prospectors, traders, and natives. In every case the most reliable source of information has been used, yet the fact that the map is in part based upon accurate surveys and in part gen eralized from verbal descriptions and sketch maps gives to its different sec tions a very unequal value and suggests that it will be subject to many correc tions in the future. However, the demand for a general map of Alaska which shall show the relief has been so great as to seem to justify the publica tion of one based only in part on accurate mensuration. A study of the diagram in the upper right-hand corner of the map will show, approximately, those parts in which the cartographic data was most reliable, the shaded spaces indicating the area in the interior of which surveys have been made. In all, about 150,000 square miles of the total area of 590,000 square miles have been surveyed, and at least two-thirds of the balance has been roughly mapped. SURVEYS AND EXPLORATIONS It would be impossible here even to outline the development of the geo graphic investigation of Alaska, which has been prosecuted intermittently since the early part of the eighteenth century, but with especial activity during the past decade. There are a few, how ever, of the more important surveys and explorations which should be men tioned. In 171 a Russian Cossack named Popof, who had been sent to the East Cape of Siberia to collect tribute from the natives, brought back an account of the islands which divide the Bering Straits, with rumors of a continent re- * Published by permission of the Director, U. S. Geological Survey.