Louis Achille Brocot (pronounced "broco") (11 July 1817 – 19 January 1878) was a French

clockmaker A clockmaker is an artisan who makes and/or repairs clocks. Since almost all clocks are now factory-made, most modern clockmakers only repair clocks. Modern clockmakers may be employed by jewellers, antique shops, and places devoted strictly to ...

. and amateur mathematician.. He is known for his discovery (contemporaneously with, but independently of, German number theorist

Moritz Stern Moritz Abraham Stern (29 June 1807 – 30 January 1894) was a German mathematician. Stern became ''Ordinarius'' (full professor) at Göttingen University in 1858, succeeding Carl Friedrich Gauss. Stern was the first Jewish full professor at a Germ ...

) of the Stern–Brocot tree, a mathematical structure useful in approximating

real number In mathematics, a real number is a number that can be used to measure a ''continuous'' one-dimensional quantity such as a distance, duration or temperature. Here, ''continuous'' means that values can have arbitrarily small variations. Every ...

s by

rational number In mathematics, a rational number is a number that can be expressed as the quotient or fraction of two integers, a numerator and a non-zero denominator . For example, is a rational number, as is every integer (e.g. ). The set of all rat ...

s; this sort of approximation is an important part of the design of

gear ratio A gear train is a mechanical system formed by mounting gears on a frame so the teeth of the gears engage. Gear teeth are designed to ensure the Pitch circle diameter (gears), pitch circles of engaging gears roll on each other without slipping, pr ...

s for clocks. Several improvements in clock design were attributed to Brocot. He invented the "Brocot Suspension", which enabled time keeping to be regulated by altering the length of the pendulum suspension spring by a key turned in the dia

He also made many practical horological innovations including refinement of his father Louis-Gabriel's pin-pallet escapement, Brocot escapement and the development of clocks with

perpetual calendar A perpetual calendar is a calendar valid for many years, usually designed to look up the day of the week for a given date in the past or future. For the Gregorian and Julian calendars, a perpetual calendar typically consists of one of three ...

mechanisms.. In order to commercially exploit his original designs, together with Jean-Baptiste Delettrez he established the clockmaking company "Brocot & Delettrez" in Paris on 20 October 1851, a partnership that would continue until his death.

References

1817 births 1878 deaths French clockmakers 19th-century French mathematicians {{france-mathematician-stub