[1] He presented a first Montre de la Mer in 1716 to the French Académie des Sciences.
[4] Henry Sully worked with Julien Le Roy, a clockmaker to Louis XV.
[5] In France, Henry Sully was followed in his developments by Pierre Le Roy and Ferdinand Berthoud.
[3] Soon after the 1726 publication of Une Horloge inventée et executée par M. Sulli, John Harrison started developing his own famous chronometer, creating a description and drawings for a proposed marine clock in 1730 and actually manufacturing the Harrison H1 in 1735.
[1] The priest of Église Saint-Sulpice, Paris, Languet de Gergy, wishing to establish the exact astronomical time in order to ring the bells at the most appropriate time of day, commissioned Henry Sully to build the Gnomon of Saint-Sulpice.