Jean-Baptiste Le Roy

Jean-Baptiste Le Roy (French pronunciation: [ʒɑ̃ batist lə ʁwa]; 15 August 1720, in Paris – 20 January 1800, in Paris) was an 18th-century French physicist and one of the major contributors to the Encyclopédie by Diderot and d’Alembert for technology.

The son of 18th-century Parisian clockmaker and watchmaker Julien Le Roy, he had three brothers: Pierre (1717–1785), a brilliant clock-maker in his own right, Julien-David (1724–1803), a neo-classical architect and archaeologist, and Charles a physician and Encyclopédiste.

In the field of science, Jean-Baptiste Le Roy worked on a variety of topics; of particular importance were his research on electricity.

Together with Patrick d'Arcy, he constructed in 1749 the first electrometer, a device for detection of electrical charges and voltages.

As contributor to the Encyclopédie, he wrote more than 130 articles under the author abbreviation "T", including those related to watchmaking, locksmith and mathematical instruments.