Greenwich in Greater London, England, United Kingdom
Time for everyone
The Royal Observatory is famous for supplying Greenwich Mean Time. From 1833, astronomers made a daily signal to mariners in the Thames at 1 p.m. (1300 hrs) by raising and dropping the time-ball on Flamsteed House. In 1852 electrical technology enabled them to send the time to the nation by telegraph. Visitors to Greenwich Park could also get the time, without disturbing the astronomers, from the Shepherd Gate Clock outside of the observatory.
The Shepherd Gate Clock is a slave dial that originally received electrical impulses from the master clock within Flamsteed House.
As the time-ball drops, air is compressed in a cylinder below, to cushion its descent to the base of the mast.
Topics. This historical marker is listed in this topic list: Science & Medicine.
Location. 51° 28.674′ N, 0° 0.087′ W. Marker is in Greenwich, England, in Greater London. Marker can be reached from the intersection of Blackheath Avenue and Great Cross Avenue, on the left when traveling north. Located at the Royal Observatory Greenwich. Touch for map. Marker is in this post office area: Greenwich, England SE10 8XJ, United Kingdom. Touch for directions.
Other nearby markers. At least 8 Airy’s meridian line (here, next to this marker); The Greenwich Meridian Telescope (here, next to this marker); Bradley’s meridian line (here, next to this marker); The Shepherd 24-hour Gate Clock (a few steps from this marker); Ordnance Survey Bench Mark (a few steps from this marker); William Herschel’s Telescope (a few steps from this marker); Greenwich Meridian Marker, 1750-1851 (a few steps from this marker); Flamsteed’s Well Telescope (a few steps from this marker). Touch for a list and map of all markers in Greenwich.
Also see . . . Royal Observatory, Greenwich on Wikipedia. (Submitted on May 24, 2018, by Michael Herrick of Southbury, Connecticut.)
Credits. This page was last revised on January 27, 2022. It was originally submitted on May 24, 2018, by Michael Herrick of Southbury, Connecticut. This page has been viewed 126 times since then and 6 times this year. Photos: 1, 2. submitted on May 24, 2018, by Michael Herrick of Southbury, Connecticut.