This regulator is illustrated in colour on the front cover of Tardy La Pendule Française, 5th edition, 1981, vol. 2 and a very similar one with hours and quarter-striking mechanism, signed: Bouchet, Horloger du Roy à Paris, is illustrated by Jean-Dominique Augarde in: Les Ouvriers du Temps, Antiquorum Editions, 1996, p. 155,fig. 122.John Arnold (1736-1799). After being apprenticed to his father in Cornwall, John Arnold established himself in London in 1760. Four years later, he presented George III with a half quarter repeating cylinder watch mounted in a ring. By the time he was 28 years old, his watches, whether verge or cylinder, displayed some original components such as straight line compensation curbs and minute repeating by increments of10 minutes instead of the more normal 15.It was towards 1768 that he had began his research into marine chronometers. In 1771 he established himself to 2 Adam Street, Adelphi Buildings, Strand, where most of his research into marine chronometers was carried out during the following eleven years. In 1776, he invented terminal curves for the cylindrical balance spring and this was included in the patent for a bimetallic compensated balance that he took out in 1782. All these earliest chronometers were fitted with a pivoted detent escapemnt. His spring detent escapement, developed from 1782, was also included in the same patent. He was admitted to the Clockmakers' Company in 1783.In 1787 he took his son, John Roger Arnold, into partnership, changing the business name to "Arnold & Son", which it retained until his death.John Roger Arnold (1769-1843) was apprenticed in Paris toA.-L. Breguet in 1792. He was admited as a member of the Clockmaker's Company in 1796, and became Master in 1817.After the death of his father, John Roger remained in business on his own until 1830, maintening the reputation gained by his father, as one of the foremost makers of his time.In 1830 he moved to 84 Strand and entered into a partnership agreement for ten years with E. J. Dent, during which period the business flourished. Much experimental work was also carried out during this period particularly on the influence of magnetism on chronometers. In 1840 Dent left Arnold, setting up next door at 82 Strand. For the following three years Arnold continued business on his own but died in Febuary 1843. Immediatly, Charles Frodsham purchased the business working under the name Anold and Frodsham until 1858.