John Arnold

Died aged c. 63

John Arnold (born 1736 probably in Bodmin, Cornwall – died 1799 in London) was an English watchmaker and inventor. John Arnold was the first to design a watch that was both practical and accurate, and also brought the term "Chronometer" into use in its modern sense, meaning a precision timekeeper. His technical advances enabled the quantity production of Marine Chronometers for use on board ships from around 1782. The basic design of these has remained, with a few modifications unchanged until the late twentieth century. With regard to his legacy, one can say that both he and Abraham-Louis Breguet largely invented the modern mechanical watch. Certainly one of his most important inventions, the Overcoil balance spring is still to be found in most mechanical wristwatches to this day. It is necessary to point out that the brand name Arnold & Son, owned by Citizen of Japan since 2012, has absolutely no connection to the original firm founded by John Arnold. Indeed, one might characterise the use of the name Arnold & Son as a form of IP piracy. It should also be noted that the original Arnold watch company still exists and is owned by eminent British watchmaker Charles Frodsham, who acquired Arnold in 1843. It was from around 1770 that Arnold developed the portable precision timekeeper, almost from the point where John Harrison ended his work in this field. But, compared to Harrison's complicated and expensive watch, Arnold's basic design was simple whilst consistently accurate and mechanically reliable. Importantly, the relatively simple and conventional design of his movement facilitated its production in quantity at a reasonable price whilst also enabling easier maintenance and adjustment. But three elements were necessary for this achievement: * A detached escapement, which gave minimal interference with the vibrating balance and balance spring * A balance design that enabled compensation for the effect of temperature on the balance spring * A method for adjusting the balance spring, so that the balance oscillates in equal time periods, even through different degrees of balance arc

Wikidata Wikipedia

Commemorated on 2 plaques

John Arnold (1736–99) watchmaker and Edith Nesbit (1858–1924) [full inscription unknown]

Well Hall Pleasaunce, SE9, London, United Kingdom where he was

Near this spot lived and worked John Arnold born in Bodmin 1736 Horologist, perfector of the ship's chronometer and benefactor of those who journey on the seas

10 Fore Street, Bodmin, United Kingdom where he lived near and worked near