Astronomy, is applied to a planet, or its orbit, to denote it concentric with the earth, or as having the earth for its centre, or the same centre with the earth.

GEOFRÆA, a genus of plants belonging to the diadelphia clas, and in the natural method ranking under the 3rd order, Papilionaceæ. See Botany and Materia Medica Index.

Geoffrey of Monmouth, bishop of St Asaph, called by our ancient biographers Gallofridus Monumentensis. Leland conjectures that he was educated in a Benedictine convent at Monmouth, where he was born; and that he became a monk of that order. Bale, and after him Pits, call him archdeacon of Monmouth; and it is generally asserted that he was made bishop of St Asaph in the year 1151 or 1152, in the reign of King Stephen. His history was probably finished after the year 1138. It contains a fabulous account of British kings, from the Trojan Brutus to the reign of Cadwallader in the year 690. But Geoffrey, whatever censure he may deserve for his credulity, was not the inventor of the stories he relates. It is a translation from a manuscript written in the British language, and brought to England from Armorica by his friend Gualter, archdeacon of Oxford. But the achievements of King Arthur, Merlin's prophecies, many speeches and letters, were chiefly his own addition. In excuse for this historian, Mr Wharton judiciously observes, that fabulous histories were then the fashion, and popular traditions a recommendation to his book.

Geoffroy, Stephen-Francis, a physician eminent for his chemical and botanical knowledge, was born at Paris in the year 1672, where his father kept an apothecary's shop, and had been several times in the magistracy. He received a liberal education; and, while prosecuting the study of medicine, he had conferences at his father's house with Cassini, du Verney, Homberg, and other men of distinguished eminence.

At Montpellier he attended the lectures of the most able 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 chief men of science, and was made a member of the Royal Society. He next went into Holland, and in 1700 he attended the abbe de Louvois in a tour to Italy. He was, on his return, made bachelor of medicine in 1702, and, in two years after, he was created M.D. One of his theses was on the question, "An hominis primordia vermis?" which was translated into French for the sake of some ladies of exalted 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 never appeared anxious to push himself forward, although his knowledge made him be often consulted by several gentlemen of the faculty. He was so concerned for the recovery of his patients, that it gave him an air of melancholy, which at first alarmed them, till they became acquainted with the cause. He was, in 1709, made professor of physic by the king to the Royal College, vacant by the death of the celebrated Tournefort. He began with lectures on materia medica; and in 1712, M. Fagon resigned to him the chemical chair: on both which topics Geoffroy lectured with unrestrained affluency. He was twice chosen to the office of dean by the faculty of Paris, and he filled a place in the Royal Academy of Sciences, from the year 1699. His health at last yielded to his toils, and he died in January, 1731. He is known to the chemical world by his table of affinities, far superior to any which had appeared before his time. His greatest work was his History of the Materia Medica, which, in an unfinished state, was published after his death in the year 1741, in 3 vols 8vo.