STEPHEN FRANCIS, a physician eminent for his chemical and botanical knowledge, was born at Paris on the 13th of February 1672, where his father kept an apothecary's shop, and had been several times in the magistracy. He received a liberal education; and, whilst prosecuting the study of medicine, he had conferences at his father's house with Cassini, Duverney, Homberg, and other men of distinguished eminence. At Montpellier he attended the lectures of the ablest professors of physic, and afterwards visited the south of France, carefully viewing every object deserving of his attention. He accompanied Count de Tallard to England in 1698, where he became acquainted with the leading men of science, and was admitted a member of the Royal Society. He next went into Holland, and in 1700 he accompanied the Abbé de Louvois in a tour to Italy. On his return, he became a licentiate in 1702, and, in two years after, he was created doctor of medicine. One of his theses was A vermis minimum ortus interitus? which was translated into French under this title, Si l'Homme a commencé par être vers for the sake of some ladies of high rank, by whom it was deemed interesting.

Geoffroy did not hastily commence the practice of medicine, continuing the prosecution of his studies in retirement for some years. He appeared nowise anxious to push himself forward, although his knowledge made him often be consulted by several gentlemen of the faculty; and he felt so concerned for the recovery of his patients, that it imparted to him an air of melancholy, which at first alarmed them, till they became acquainted with the case. In 1709, he was appointed by the king professor of physic to the Royal College, vacant by the death of the celebrated Tournefort, and began with lectures on Materia Medica; but in 1712, Fagon resigned to him the chemical chair, and on both subjects Geoffroy lectured with unremitting assiduity. He was twice chosen as dean by the faculty of Paris, and from the year 1699 he filled a place in the Royal Academy of Sciences. Anxious to discharge his various functions with credit, his health at last sank under fatigue, and he died upon the 5th of January 1731. He is known to the chemical world by his table of affinities, which is far superior to any that had appeared before his time. His greatest work was his History of the Materia Medica, which was published in an unfinished state, after his death, Paris, 1741, in 3 vols. 8vo. This learned and laborious author enriched the Mémoires of the Academy of Sciences with different articles, the principal of which were, 1. Table des Différents Rapports observés en Chimie entre différents Substances, and Éclaircissements sur cette Table, 1718 and 1720; 2. Observations sur le Vitriol et sur le Fer, 1713; 3. Sur les Dissolutions et sur les Formations que l'on peut appeler froides, parce qu'elles sont accompagnées du refroidissement des Liqueurs dans lesquelles elles se passent, 1700; 4. Examen des eaux de Vichy et de Bourbon l'Archambault, 1702; 5. Détail de la manière dont se fait l'Alun de roche en Italie et en Angleterre, 1702.