A victory in such a competition was considered highly honourable, and the winner was permitted to put the special symbol of an anchor on his watches. In the 16 th – 19 th centuries, high-profile competitions between watchmakers occurred, for who could make the most accurate chronometer. The creation of ship’s chronometers has made a huge contribution to the history of the development of mechanisms for accurate time measurement. Therefore, before sailing, all ship’s chronometers were synchronised with the Greenwich time according to the observatory’s standard reference time.
Of course, the more accurate the ship’s reference chronometer, the more accurate the determination of the ship’s position on the chart. The coordinate is then calculated based on the difference between the readings, so for every four minutes that Greenwich time differed from the local time observed on board via the sundial, the ship had travelled on longitudinal degree. To find out the longitudinal angle, one needs to have the readings from two clocks – a sundial, and a reference chronometer set to Greenwich time.
Finding the latitude is fairly simple – it can be determined by the angle of the position of the North Star in relation to the horizon, but determining the longitude is a bit more complicated.įor every hour, the earth rotates 15 degrees relative to the sun (by 24 hours it will have made a full 360-degree rotation). In order to navigate nautical charts, one needed to know the exact coordinates of the vessel, latitude and longitude. To determine the approximate age of your watch, open the case and find the serial number, usually found engraved on the movement or the case back itself, then match it up with the list on this page.Ĭross reference the Movement number with the case number to find the time scale of when your watch was produced.Small Marine Chronometer, Longines-Wittnauer 1932, Switzerlandĭue to the absence of modern GPS systems and reliable long-range radio, sea voyages were unsafe without an accurate time meter. Should you require a more conclusive valuation of your time piece then please do not hesitate to email us. Please remember that this is just an approximate guide and can not be used as a 100% accurate outlook as per how old your watch might be.