1870 U.S. Coast Survey Map Showing Magnetic Declination in the United States
|
|
|
Description: A highly unusual U.S. Coast Survey chart of the United States showing magnetic declination in the year 1870. Magnetic Declination, or as it is more commonly known Magnetic Variance, refers to the difference between true north and compass north. Magnetic variance changes both over time and from place to place, consequently accounting for compass errors was a major obstacle for many early cartographers. Today the magnetic variance in Florida is 0 degrees, but when this chart was made in 1870, the 0 degree point was in South Carolina. A cartographer traveling north from South Carolina to Maine would find that his compass miscalculated north by nearly 18 degrees! In other places the variance is even more extreme. Compiled under the direction of A. D. Bache, Superintendent of the Survey of the Coast of the United States and one of the most influential American cartographers of the 19th century.
Date: 1870 (dated)
Source: Report of the Superintendant of the United States Coast Survey, Washington, (1870 edition).
Cartographer: The Office of the Coast Survey, founded in 1807 by President Thomas Jefferson and Secretary of Commerce Albert Gallatin, is the oldest scientific organization in the U.S. Federal Government. Jefferson created the "Survey of the Coast," as it was then called, in response to a need for accurate navigational charts of the new nation's coasts and harbors. The first superintendent of the Coast Survey was Swiss immigrant and West Point mathematics professor Ferdinand Hassler. Under the direction of Hassler, from 1816 to 1843, the ideological and scientific foundations for the Coast Survey were established. Hassler, and the Coast Survey under him developed a reputation for uncompromising dedication to the principles of accuracy and excellence. Hassler lead the Coast Survey until his death in 1843, at which time Alexander Dallas Bache, a great-grandson of Benjamin Franklin, took the helm. Under the leadership A. D. Bache, the Coast Survey did most of its most important work. During his Superintendence, from 1843 to 1865, Bache was steadfast advocate of American science and navigation and in fact founded the American Academy of Sciences. Bache was succeeded by Benjamin Pierce who ran the Survey from 1867 to 1874. Pierce was in turn succeeded by Carlile Pollock Patterson who was Superintendent from 1874 to 1881. In 1878, under Patterson's superintendence, the U.S. Coast Survey was reorganized as the U.S. Coast and Geodetic Survey (C & GS or USGS) to accommodate topographic as well as nautical surveys. Today the Coast Survey is part of the National Oceanic and Atmospheric Administration or NOAA. Click here for a list of rare maps from the U. S. Coast Survey.
Size: Printed area measures 20 x 14.5 inches (50.8 x 36.83 centimeters)
Condition: Very good. Minor wear, toning, and verso reinforcement on some of the original fold lines. Blank on verso.
Code: MagneticDeclination-uscs-1870 (Necessary for phone inquiries: 646-320-8650)
|