EGIDIO

FORCELLINI (1688-1768)  , Italian philologist, was born at Fener in the district of Treviso and belonged to a very poor family . He went to the seminary at Padua in 17o4, studied under Facciolati, and in due course attained to the priesthood . From 1724 to 173 he held the office of rector of the seminary at Ceneda, and from 1731 to 1765 that of father confessor in the seminary of Padua . The remaining years of his life were reflections in rhombs of rock-salt . His work won him the Rumford medal of the Royal Society in 1838, and in 1843 he received its Royal medal for a paper on the " Transparency of the Atmosphere and the Laws of Extinction of the Sun's Rays passing through it." In 1846 he began experiments on the temperature of the earth at different depths and in different soils near Edinburgh, which yielded determinations of the thermal conductivity of trap-tufa, sandstone and pure loose sand . Towards the end of his life he was occupied with experimental inquiries into the laws of the conduction of heat in bars, and his last piece of work was to show that the thermal conductivity of iron diminishes with increase of temperature . His attention was directed to the question of the flow of glaciers in 184o when he met Louis Agassiz at the Glasgow meeting of the British Association, and in subsequent years he made several visits to Switzerland and also to Norway for the purpose of obtaining accurate data . His observations led him to the view that a glacier is an imperfect fluid or a viscous body which is urged down slopes of a certain inclination by the mutual pressure of its parts, and involved him in some controversy with Tyndall. and others both as to priority and to scientific principle . Forbes was also interested in geology, and published memoirs on the thermal springs of the Pyrenees, on the extinct volcanoes of the Vivarais (Ardeche), on the geology of the Cuchullin and Eildon hills, &c . In addition to about 150 scientific papers, he wrote Travels through the Alps of Savoy and Other Parts of the Pennine Chain, with Observations on the Phenomena of Glaciers (1843); Norway and its Glaciers (1853); Occasional Papers on the Theory of Glaciers (1859) ; A Tour of Mont Blanc and Monte Rosa (1855) . He was also the author (1852) of the " Dissertation on the Progress of Mathematical and Physical Science," published in the 8th edition of the Encyclopaedia Britannica . at Cuttlebrae, Banffshire, in 1787 .

He attended the

grammar school at Aberdeen, and afterwards entered Marischal College . After serving Par nine years as a surgeon in the navy, he graduated M.D. at Edinburgh in 1817, and then began to practise in Penzance, whence he removed to Chichester in 1822 . He took up his residence in London in 1840, and in the following year was appointed physician to the royal household . He was knighted in 1853, and died on the 13th of November 1861 at Whitchurch in Berkshire . Sir John Forbes was better known as an author and editor than as a practical physician . His works include the following: Original Cases . . illustrating the Use of the Stethoscope and Percussion in the Diagnosis of Diseases of the Chest (1824) ; Illustrations of Modern Mesmerism (1845); A Physician's Holiday (1st ed., 1849); Memorandums made in Ireland in the Autumn of 1852 (2 vols., 1853); Sight-seeing in Germany and the Tyrol in the Autumn of 1855 (1856) . He was joint editor with A . Tweedie and J . Conolly of The Cyclopaedia of Practical Medicine (4 vols., 1833—1835); and in 18'6 he founded the British and Foreign Medical Review, which, after a period of prosperity, involved its editor in pecuniary loss, and was discontinued in 1847, partly in consequence of the advocacy in its later numbers of doctrines obnoxious to the profession .