Universal ring dial

Date1700-1752

Object number00004858

NameUniversal ring dial

MediumBrass

DimensionsOverall: 134 x 115 x 102 mm, 0.15 kg

ClassificationsTools and equipment

Credit LineANMM Collection

Terms

DescriptionThis 18th Century Universal ring dial was used to tell local time at any location during daylight. It consists of two brass rings one inside the other. Despite the invention of clocks in the 19th Century, ring dials were still used for navigation and to calibrate early mechanical clocks. This type of ring dial is called universal because it can be used in any latitude.HistoryDuring the 18th century explorers were attempting to discover and map the world’s oceans and continents. In order to achieve this they needed instruments that accurately defined their location at any given time. Universal ring dials were a popular device used primarily from the 1600s to 1800s to tell the time at sea during daylight. The universal ring dial differed from the sundial due to its ability to self correct and remain steady during small ocean swells. When used with a Nocturnal, used to measure time at night, it was possible to record accurate time for a 24 hour period. Despite the invention of the mechanical clock, universal ring dials were still used in the early 1900s for navigation. SignificanceThe Universal ring dial is an example of the navigational instruments used by sailors and explorers during the 17th and 18th centuries. This equipment became a standard navigational tool on all ships at the time.