Type of clock: Riefler astronomical clock Clock maker: Riefler Location: Ladd Observatory Catalogue number: no historic property number visible Country: Munich Date: ca. 1902 Marks: L. Riefler DRPNo. 50739 No. 35/Munchen DRPNo. 60059 1898 Donor's Plaque: Presented to the Ladd Observatory by the Class of 1875 in 1902 Restoration Plaque: Restoration of Riefler #35 dedicated to the memory of Gerald M. Clemence, Class of 1930
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Description: Made of steel, glass, and brass, this clock is housed in a clock vault below the Observatory's dome, which is completely isolated from the rest of the 1891 building by a gap that prevents any disturbance. The clock is hermetically sealed in a long glass cylinder jar and maintained at constant temperature and vacuum, thus eliminating barometric pressure correction. Air could be introduced into or exhausted out of the clocks to slow down or increase their rates, respectively. Provenance: This clock was presented to the Ladd Observatory by the Class of 1875 in 1902 and was restored in memory of Gerald M. Clemence, Class of 1929. Dr. Clemence received his bachelor of science in mathematics from Brown University and honorary doctorates from the Case Institute of Technology and from the University de Cuyo in Argentina. He served in the U.S. Naval Observatory from 1930 to 1963. In 1963, he received the Conrad Award "for outstanding contributions to celestial mechanics theory ... being foremost in his field ... greatly assisted the Navy and this Nation ..." As Scientific Director of the Naval Observatory 1958-1963, and Chief of Naval Operations and Research, his leadership as scientist and administrator helped make possible the high prestige with which the U.S. Navy and Naval Observatory are held throughout the world. In 1965, while serving as Senior Research Associate and Lecturer at the Department of Astronomy at Yale, he received the Gold Medal of the Royal Astronomical Society of London, considered the most distinguished international prize in astronomy Clemence died on November 22, 1974 in Hallworth House, Providence, after an eight-month illness. Born in Smithfield on August 16, 1908, he lived in Johnston before and after his career in Washington. Clockmaker biography: Siegmund Riefler was born in Munich and died in 1912, aged 65. He was the inventor of the Riefler compensated pendulum and escapement for observatory clocks in 1891. These astronomical clocks were recognized as the time standard from 1904 through 1929, when the Shortt clock replaced it. [1] Related information: The telescope at the Observatory is run by a clock mechanism as well. The clock drive, which made the telescope revolve, was made by G.N. Saegmuller of Washington Ladd Observatory was opened on October 21, 1891 through the munificence of Governor Herbert W. Ladd and Brown University's President Robinson. From the beginning the observatory had three purposes: instruction in astronomy for the students, service to astronomical research, and furnishing of time signals. From 1893 to 1973 Ladd Observatory provided time signals, first to the Rhode Island Electric Protective Company, which distributed them throughout the state, then in 1906 to the local fire stations. The transit observations were discontinued in November 1916 and began again after the war in 1919. The observatory continued to send out its time signals for years, discontinuing the practice only when it was observed that no one was receiving them. References: [1] Britten, J.F. Old Clocks and Watches and Their Makers. (Fifth edition) E. & F.N. Spon Limited, 57 Haymarked, S.W. 1922, p. 766.