The repeating circle is an instrument for geodetic surveying, developed from the reflecting circle by Étienne Lenoir in 1784.[1] He invented it while an assistant of Jean-Charles de Borda, who later improved the instrument. It was notable as being the equal of the great theodolite created by the renowned instrument maker, Jesse Ramsden. It was used to measure the meridian arc from Dunkirk to Barcelona by Jean Baptiste Delambre and Pierre Méchain (see: meridian arc of Delambre and Méchain).
- ^ Daumas, Maurice (1989). Scientific Instruments of the Seventeenth and Eighteenth Centuries and Their Makers. London: Portman Books. ISBN 978-0-7134-0727-3.