Browse Chronometers on Chrono24

Though the Swiss set the standard, the English coined the word. In the quest to calculate the longitude, the Englishman Jeremy Thacker, a clockmaker of extraordinary skill, created a series of increasingly accurate clocks, well beyond what had had previously been achieved. The clocks were intended to be used aboard ships and had to keep absolutely accurate time in order to allow for calculating longitude precisely, and thus fixing the position of the ship in the vast ocean. The last of Thacker’s chronometers was actually more like a very large pocket watch.

Other clockmakers – and increasingly watchmakers – copied from and improved upon Thacker’s final chronometer, producing watches of greater and greater precision. The original standards for accuracy were actually far more exacting than those currently maintained by the COSC in Switzerland, so very few watches were certified as chronometers and thus very few were actually produced and sold. The original chronometer requirements for mechanical watches are no longer necessary, since digital watches can already exceed them, but chronometers are still manufactured and sold (and resold) today as examples of extremely fine precision engineering. The use of jewels and precious metals in watches owes its origins to chronometers – these materials were used to make the mechanical movements as precise as possible.