Learn about Marine Chronometer
A marine chronometer is a clock with a highly accurate time-keeping mechanism that can be used to determine longitude by means of celestial navigation..
They were essential navigational instruments for mariners and used in conjunction with the sextant they can determine an accurate calculation of the latitude and longitude of a vessel.
Prior to the invention of the chronometer in the 18th century, there was no reliable method for determining longitude, (although latitude could be calculated) with the result that ships could end up many miles east or west from their proposed destination, and even worse, run aground on land or reefs.
Credit for the invention of the chronometer is given to John Harrison, originally a Yorkshire carpenter, who spent most of his working life perfecting the invention.
Chronometers are usually mounted on gimbals and housed in a highly polished block-shaped wooden case often with protective brass edges, handles and a viewing lid. Emphasising the importance placed on safeguarding the chronometer, this was then second felt-lined wooden case. more...