Timekeeping

The National Maritime Museum specializes in precision timekeeping. With over 1000 objects, it is the finest collection of its kind in the world.

The collection includes precision pendulum clocks (regulators), marine chronometers and deck watches. Especially notable are the famous and seminal series of timekeepers by John Harrison (1693-1776). Time distribution devices include the original Shepherd master and slave system, the famous time ball by Maudsley on the Royal Observatory, Greenwich (ROG) roof and the original regulators generating the BBC 'six-pip' signals.

The collection also contains a large number of timepieces with complex astronomical indications, clocks and watches associated with famous naval figures and events and a growing selection of domestic timekeepers. Supporting these fine collections are relevant historical notes, including the Admiralty's records relating to the trials and issues of chronometers. These manuscript ledgers are the basis of the International Chronometer Index (ICI) maintained at the ROG since 1970 to record data on all surviving marine chronometers worldwide.