NAUTICAL CHART USER’S MANUAL
U.S. DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration (NOAA) National Ocean Service
Washington, DC, 1997
It would appear that on some [of the Marshall Islands]
these charts were considered so precious that they might not be taken to sea. This was partly because they mightbe damaged in the canoes and partly, perhaps, because the people might never come back, in which case the tribes precious property would be lost for ever. [Emphasis added.] Collinder
Background Marine transportation is crucial to the United States economy: according to data published by the U.S. Bureau of the Census, in 1991 approximately 99 percent ofall U.S. trade by weight (48 percent by value) was waterborne. And safe operation is essential to marine transportation. Accidents result in injuries, cost lives, and increase insurance rates. Moreover, as the Amoco Cadiz, Argo Merchant, Exxon Valdez, and Torrey Canyon cases vividly demonstrated, accidents have the potential to cause significant environmental damage (Cahill, Keeble, Marriott,Nalder, Petrow, Winslow). Fortunately, the operational safety of ships, measured in terms of marine casualties (including ship losses, tonnage lost, and volume of oil spilled), has increased over the past several decades [National Research Council (NRC) 1994 b]. Accurate and up-to-date nautical charts are the most basic navigational aidso basic, in fact, that carriage of corrected charts is a legalrequirement for certain classes of vessels. The need for accurate charts was recognized early in the history of the United States. The situation in the early days was described by one observer (Stanley 1976):
Moreover, young America at the turn of the 19th century was experiencing a tremendous growth in maritime commerce. Heavily laden cargo vessels and passenger ships with their preciousburdens were entering and departing American ports for all parts of the world
Charts then in existence consisted chiefly of those produced by the British Admiralty of Colonial America for use prior to and during the American Revolution. These charts were based upon vague and incomplete reports and sketches, and were totally inadequate for needs of the times. In 1807, Congress passed the Organic Actauthorizing President Thomas Jefferson
to cause a survey to be taken of coasts of the United States, in which shall be designated the islands and shoals, with the roads or places of anchorage, within 20 leagues [approximately 60 miles] of any part of the shores of the United States; and also the respective courses and distances between the principal capes or head lands, together with such othermatters as he may deem proper for completing an accurate chart of
every part of the coasts within the extent aforesaid. In 1834, the Survey of the Coast, since renamed the Coast Survey (in 1936), the Coast and Geodetic Survey (in 1871), the National Ocean Survey (in 1970), and the National Ocean Service (in 1982), completed its first hydrographic survey of Great South Bay, Long Island,NY. The first U.S. Government produced nautical chart, a blackand-white print made from a stone engraving of Bridgeport Harbor, CT, was issued in 1835. Charts were not routinely produced until 1844, a year in which 169 copies were sold (Stanley 1974). Chart sales grew to 50,000 copies about the time of the Civil War, and 100,000 copies by the year 1900. Schooners were employed as survey ships inthose days, leadlines (a line, marked at graduated intervals, with a lead weight attached at one end) were cast at intervals to gather data on water depths, and dead reckoning (DR) and celestial navigation methods were used to fix the survey ships position when out of sight of land. Primitive as these systems were, the results were useful and the charts based upon these surveys contributed...
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