Horace Bénédict de Saussure (1740-1799), seated under a pine tree with snowy mountain in the background, in grey jacket, yellow waistcoat with covered yellow buttons, knotted white cravat, orange cloak draped around his shoulders and over his legs, holding a large hammer in his left hand and a mineral specimen in his right hand, the spine of a green covered book entitled 'De Saussure Professeur 1784' lying on a rock beside him with Alpine flowers and a hygrometer suspended from a wooden pole

Horace-Bénédict de Saussure was a Swiss physicist, geologist and early Alpine explorer who developed the hair hygrometer and probably the first electrometer. Born in Conches, the son of Nicolas de Saussure, a country gentleman interested in agricultural matters who published several practical treatises on cultivation, pruning, crop failures and soil fertility, Horace-Bénédict was educated in the public school of Geneva and at the Academy of Geneva. In 1762, he became Professor of Philosophy and Natural Sciences where he founded the Société pour l'Avancement des Arts. On his first visit to Chamonix in 1760, he viewed Mont Blanc and was so determined that it would be climbed he offered prize money for the ascent. This was not claimed until 1786 by Michel-Gabriel Paccard from Chamonix and his porter, Jacques Balmat. De Saussure himself reached the summit a year later on 3 August 1787 with Balmat. He crossed the Alps fourteen times and his work 'Voyage dans les Alpes' (1779-96) contains more than 30 years of geologic studies. The genus of high Alpine plants 'Saussurea' is named after him and the standard botanical author abbreviation Sauss. is applied to the species he described. He carried barometers and boiling-point thermometers to the summits of the highest mountains and invented and improved many of these instruments including the magnetometer, the cyanometer (to determine the blueness of the sky), the diaphanometer (for judging the clearness of the atmosphere), the anemometer and the mountain eudiometer. In 1767 he constructed the first Western solar oven and in 1783 he built the first hygrometer using human hair to measure humidity. He married Albertine Boissier and one of his sons, Nicolas Théodore (b. 1767) was also a scientist who is amongst those responsible for founding the modern theory of plant nutrition. He is buried in the cemetery of Plainpalais in Geneva.
This is copied after the large scale oil portrait by Jean-Pierre Saint-Ours (1752-1809), commissioned in 1795 by the Société des Arts, Geneva, of which de Saussure was a founding member. The portrait, signed and dated 1796, is part of the collection of the Société des Arts, Geneva. A signed version of this enamel was in the Holzscheiter Collection, part II, sold Sotheby's, London, 1 May 1980, lot 36. Two later reduced versions, one by Marc Henry and one by Jean-François Victor Dupont (1822) are in the Musée de l'Horlogerie et de l'Emaillerie, Geneva. A circular enamel of the sitter formerly in the David-Weill Collection was in the Clore Collection, part I, sold Sotheby's, London, 17 March 1986, lot 152 (as by Nicolas André Courtois).