Object notes Associations
Sidereal clock (regulator) marked "E. Howard & Co., Boston".
This was one of eight precise sidereal clocks made for the American Transit of Venus expeditions of 1874. It was also used by Albert Michaelson in 1883 for his speed of light experiments at the Case School of Science in Cleveland. Gravity escapement, mercury pendulum, weight driven, one-second break circuit, mercury cup.
Catalog no. 319.996 Mechanisms Collection Smithsonian Institution
Object contributed by National Museum of American History, Smithsonian Institution