Senebier, Jean (1742–1809)

Swiss botanist, plant physiologist, and pastor, whose research on photosynthesis (the process by which green plants use light energy to make carbohydrates) showed that ‘fixed air’ (now known to be carbon dioxide) was converted to ‘pure air’ (oxygen) in a light-dependent process.

His work on photosynthesis was a forerunner of Claude Bernard's work in the early 1800s. Senebier showed that it was the light and not the warmth of sunlight that was necessary for photosynthesis to occur, and that photosynthesis does not occur in boiled water from which the gases have been excluded. His Action de la lumiére sur la végétation 1779 is an important paper on photosynthesis.

Senebier was born in Geneva. Although he developed an interest in botany from an early age, he was ordained as a pastor in the Protestant church of Geneva 1765 in order to please his family. He was appointed pastor of Chancy near Geneva 1769. Prior to taking up this appointment, he had travelled to Paris, where he conducted several experiments in plant physiology. In 1769, he was made librarian for the Republic of Geneva. He was able to continue with his research and developed a reputation as a plant physiologist. He taught Pierre Huber, Augustin Pyrame de Candolle, and Nicholas Theodore de Saussure.