The old United States Naval Observatory, currently known as Building 2 Potomac Annex, is listed on the National Register of Historic Places (1966) and is a National Historic Landmark.
The Naval Observatory operated on Observatory Hill from 1844 to 1893 and was a symbol of success in America's early struggle for intellectual, scientific and technological independence from Europe. As an institution, it represented the young nation's aspirations to take its place in the world scientific community. It also allowed America to generate its own astronomical data without reliance on Europe; an important step in developing independence in navigation and whaling, two endeavors critical to the commercial success of the courtly in the nineteenth century. Instituting a national observatory enjoyed the support and sustained the attention of American's leaders from the beginning, including Presidents Thomas Jefferson and John Quincy Adams.
Significant discoveries, functions and events associated with the National Observatory include both navigational as well as astronomical pursuits. The Observatory was responsible for cataloging locations of stars and planets. It was also designed to rate maritime chronometers for accuracy. As telegraphic technology developed, the Observatory functioned as the nation's official time-keeper, standardizing the measurement of time throughout most of the country. Matthew Fontain Maury (Director from 1844-1861) made contributions to the fields of navigation and oceanography, particularly his publication of the "Abstract Log for the Use of American Navigators" (1848) and "The Physical Geography of the Sea" (1855).
Its middle history, between the years 1893 and 1942, allowed "Observatory Hill" and its anchor building to mature into new uses with new occupants including the Naval Museum of Hygience and, later, the Naval Medical School and Hospital. These later developments enhance the significance of the site, both through the quality of architecture and through the important role the School and Hospital played as the Navy's medical headquarters in the Nation's Capital. Potomac Annex currently functions as administrative offices for the Naval Bureau of Medicine and Surgery and serves as headquarters of the Surgeon General of the Navy.
Although changed by many alterations and additions, much of the original structure exists as the central core of the building. The late-Greek Revisal style of the original building core reflects the architectural taste of the the 1840s when the building was constructed. It was an appropriate institutional style and symbolized the democratic aspirations of the young country. Though there was no formally trained architect for the building, great care was given to the building's final form. In 1838, Lieutenant James Melville Gillis was promoted to director of the Deport of Charts and Instruments. As Director, Lieutenant James Mellvlle Gillis was responsible for overseeing the construction of the Observatory. With no formal astronomical training, he sought the advice of director of the leading observatories of the day, including observatories in London, Oxford, Cambridge, Dublin, Hamburg, Berlin, Leipzig, and Munich. His search provided him with a plan that incorporated the most appropriate dimensions suitable for the instruments of a working observatory. Gillis hired an English draftman to draw plans according to his specifications.
The Observatory's Greek Revival Style was reflected, and sometimes simply replicated, in detail as new additions were made to the building. The quality of the design and construction, as well as the unusual technological requirements of the ordinal observatory building, render it a significant contribution to American architecture. The attention and respect paid to the original design intent during subsequent construction makes the whole a comprehensive and pleasing architectural composition.
Specific Significance Years: 1843, 1893
Area of Significance: Military science