OZIAS

HUMPHRY (1742-1810)  , English miniature painter, was born at Honiton and educated at the Grammar School of that town . Attracted by the gallery of casts opened by the duke of Richmond, Humphry came to London and studied at Shipley's school; and later he left for Bath, where he lodged with Linley and became a great friend of his beautiful daughter, afterwards Mrs Sheridan . In 1766 he was in London warmly encouraged by Sir Joshua Reynolds, who was always interested in Devonshire painters . He was a great friend of Romney, with whom in 1773 he went to Italy, staying, on his way to Dover, at Knole, where the duke of Dorset gave him many commissions . In 1785 he went to India, visiting the native courts, painting a large number of miniatures, and making many beautiful sketches . His sight failed him in 1797, and he died in Hampstead in 181o . The bulk of his possessions came into the hands of his natural son, William Upcott, the book collector . From him the British Museum acquired a large number of papers relating to Humphry . He was Opie's first master, and is alluded to in some lines by Hayley . His miniatures are exquisite in detail and delightful in colouring . Many of the finest are in the collection of Mr J . Pierpont Morgan .

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History of Portrait Miniatures, by G . C . Williamson, vol. ii . (London, 1904) . (G . C . W.) HUMUS (a Latin word meaning the ground), a product of decomposing organic matter . It is especially present in peat bogs, and also occurs in surface soils, to which it imparts a brown or black colour . It is one of the most important soil-constituents from the agricultural point of view; it is the chief source of nitrogenous food for plants, and modifies the properties of the soil by increasing its water-holding capacity and diminishing its tenacity . Little is known with regard to its chemical composition . By treating with a dilute acid to remove the bases present, and then acting on the residue with ammonia, a solution is obtained from which a mineral acid precipitates humic acid; the residue from the ammonia extraction is termed humin . Both the humic acid and humin are mixtures, and several constituents have been separated; ulmic acid and ulmin,in addition to humic acid and humin, are perhaps the best characterized .