John Arnold (1736-1799): Born in Cornwall, son of a clockmaker.
1764: workshop set up in the Strand, London.
Minute repeater-ring gift to King George III, gains access to circles of wealthy people. Joins the Longitude Act competition: find a reliable method for calculating longitude at sea to stop heavy maritime losses and accelerate the expansion of Britain’s empire.

Specializes: Marine Chronometers 1770’s:
stricter rules decreed for watchmaker-longitude method proposals: 2 identical prototypes and tests both at sea and on land Arnold’s vision, entrepreneurial skills and technical genius gives him the edge over competitors, co-wins the Longitude Prize Son John Roger joins the firm, studies for a year with his father’s friend in Paris: A.L. Breguet.

Invents a revolutionary production process Inventor of detent escapement and substantial movement simplification.
Maker of the first ever pocket chronometer (N°36).
Arnold & Son becomes by far the leading supplier to the Royal Navy.

Arnold chronometers accompany numerous famous British explorers: Cook, Phipps, Vancouver, Flinders, Dr. Livingstone, John Franklin, Sir Ernest Shackleton, etc.