This is an uncommon 1941 World War II era map or nautical chart of Hatta-Retto or the Rover Group by the U.S. Navy Hydrographic Office. This chart covers the Islands of Pachau and Tsiang. Hatta-Retto or modern day Wang-an subdivision is part of the Pescadores or Penghu Islands located off the western coast of Taiwan or Formosa, in the Taiwan Strait. Based on Japanese surveys in 1896, with additions to 1941, this chart offers extraordinary detail throughout including topography. The map shows considerable inland detail for a nautical chart, noting buildings, towns, hills, etc. The chart includes countless depth soundings in fathoms as well as notes on currents and other practical information for the mariner. An elevation profile is included along the left margin. First issued in 1912, the map, in this state, has been updated to 1941. Issued as chart no. 2641 by the U.S. Navy at the Hydrographic Office under the authority of the Secretary of the Navy.
The U.S. Navy Hydrographic Office (1830 - 1962) is a branch of the United States Navy founded in 1830 to compile non-domestic hydrographic and bathymetric surveys. These surveys are conducted by the U.S. Naval Oceanographic Office, which started with the establishment of the Depot of Charts and Instruments in 1830. In 1854 the U.S. Navy Oceanographic Office was renamed the U.S. Naval Observatory and Hydrographical Office. The hydrographic portion became the U.S. Naval Hydrographic Office under the Hydrographer of the Navy. In 1962, under the Kennedy administration, the name was again changed to the U.S. Naval Oceanographic Office in 1962. That office, as a matter of historical and semantic interest, and the U.S. Naval Observatory are still part of the command overseen by the "Oceanographer of the Navy" with headquarters at the Naval Observatory in Washington D.C.
Very good. Minor wear along Original fold line.