In 1807, Congress authorized a survey of the coasts of the United States to designate what places ships could anchor.
In 1842, construction of a permanent building for the Navy's Depot of Charts and Instruments was authorized with the passage of Bill No. 303 of the 27th Congress.
Matthew Fontaine Maury
Navy Lieutenant Matthew Fontaine Maury was first Superintendent of the Navy's Depot, and he began the first formal scientific investigations of the deep ocean environment. Maury was convinced that his chief duty should be the preparation of ocean charts. At the time, most charts on naval vessels were found to be over 100 years old and quite useless.Hydrography
A major goal of Matthew Fontaine Maury was to assert the United States Navy's independence from the British Admiralty and to make their own national contribution to hydrography - the practice of nautical surveying and charting.
Wind and Current Charts
Under Maury's direction, hundreds of ships' logs that were stored in the Navy's warehouses were hauled out and studied. By comparing the logs of ships on a particular route, Maury pinpointed locations where extremes and differences occurred in ocean conditions, and he was able to suggest certain areas of the oceans that should be avoided at different times of the year. The result was Maury's famous Wind and Current Charts, which soon became indispensable to mariners of all nations.Maury also devised an "abstract log" like a template on which to work, which was suppled to all Navy ships. Navy captains were required to complete these logs for each voyage, while merchant and foreign vessels did so on a voluntary basis. In exchange for sending him their completed logs, Maury would send his Wind and Current Charts to participating ships' captains, and they had an immediate effect on ocean commerce. Using Maury's information, for example, clipper ships were able to shave 47 days off the passage from New York to San Francisco, resulting in savings of millions of dollars annually.
The Telegraph
With the invention of telegraphy and the resulting desire to connect the continents with deep sea cables, ocean surveys of the North Atlantic soon commenced. During these surveys, the first geological specimens were brought up from the ocean floor. Within a few years, the first depth chart of the Atlantic Ocean was published, and in 1858, the first successful transatlantic cable was laid down.
Celestial Navigation
Another activity of the Depot of Charts and Instruments was the collection and collation of star positions, useful for celestial navigation. After the Civil War, the nautical charting functions of the Observatory separated from the Observatory and became the Naval Hydrographic Office, a precursor of today's Naval Oceanographic Office.The Observatory’s greatest fame came during these post-Civil War years, and culminated with the discovery there of the moons of Mars in 1877 by astronomer Asaph Hall.
