Page:Encyclopædia Britannica, Ninth Edition, v. 17.djvu/851

P I O P I 787 red lines, the arteries paler and about two-thirds the size of the darker veins. They arise in the centre of the disk, run usually in pairs, branching as they pass over the retina. Note their light central streak, their amount of tortuosity, and the presence or absence of white lines by their side. (C) Note the usually uniform redness of the choroid. In light-haired and dark-haired persons the vessels appear as dark or light red bands on the general red ground. (D) The yellow spot is indicated either by a deeper redness of the choroid or by a bright yellow spot surrounded by a shifting white halo. By the direct method the mirror is used without the large lens, if necessary, one of the smaller lenses being placed behind the cen tral perforation. (A) Examine the crystalline lens (see "cataract " above). (B) Opacities in the vitreous humour are detected as mov ing bodies when the eye is moved about and then brought to a standstill. (C) Ascertain the refraction. The eye is ametropic if the vessels are seen distinctly at more than 18 inches distance. It is hypermetropic if the observer on moving his head finds the vessels moving in the same direction ; myopic if they go the opposite way. To measure the amount of ametropia needs practice and power of the observer to relax his accommodation completely. Rays leaving the hypermetropic eye are divergent ; to be seen clearly by the observer they must be rendered parallel. The strongest convex lens, therefore, which, placed behind the central aperture, gives a clear image of the fundus is the measure of the hypermetropia. Similarly the lowest concave lens with clear image indicates the amount of myopia. (D) To examine the details of the fundus, the mirror is approached closely to the observed eye. Retinoscopy. The observer sitting at a distance of 4 feet from the patient reflects the light into his eye, after dilating the pupil with atropine, and rotates the mirror slightly. A shadow will be seen to cross the pupil, in myopia of more than ID ( T V) in the same direction as the rotation, in all other cases in the opposite direc tion. This method is useful in determining and correcting the refraction where the patients are too young or too stupid to assist with their answers. (A. BR. ) OPIE, AMELIA (1769-1853), the wife of John Opie, noticed below, was the daughter of Dr Alderson, a phy sician in Norwich, and was born there in 1769. The cir cumstances of her early life gave the bent to her after-career. In her girlhood she beguiled the solitude of her father s summerhouse by composing songs and tragedies ; on her visits to London the superior society into which the accom plishments of her mind and the graces of her person intro duced her served to stimulate her aspirations ; and after her marriage in 1798 she was encouraged by her husband to become a candidate for literary fame. Accordingly, in 1801 she published a novel entitled Father and Daughter. Although this tale showed no artistic ability in dealing either with incidents or with characters, yet it was the work of a lively fancy and a feeling heart, and speedily brought its author into notice. She was encouraged to publish a volume of sweet and graceful poems in 1802, and to persist in the kind of novel -writing which she had so successfully commenced. Adeline Mowbray followed in 1804, and Simple Tales in 1806. The death of her husband in 1807 and her return to Norwich did not slacken her industry. She published Temper in 1812, Tales of Real Life in 1813, Valentine s Eve in 1816, Tales of the Heart in 1818, and Madeline in 1822. At length, in 1825, her assumption of the tenets and garb of the Quakers checked her literary ardour and changed her mode of life. Beyond a volume entitled Detraction Displayed, and several contributions in prose and verse to various periodicals, nothing afterwards proceeded from her pen. The rest of her life was spent in travelling and in the exercise of Chris tian benevolence. She died at Norwich in 1853. A Life of Mrs Opie, by Miss C. L. Bright well, was published in 1854. OPIE, JOHN (1761-1807), historical and portrait painter, was born at St Agnes near Truro in May 1761. He early showed a taste for drawing, and for scholarship also, hav ing at the age of twelve mastered Euclid and opened an evening school for arithmetic and writing. Before long he Avon some local reputation by portrait -painting; and in 1780 he started for London, under the patronage of Dr Wolcot (Peter Pindar), who hoped to win credit, and still more substantial benefits, from the fame of his young protege. Opie was introduced to the town as "The Cornish Wonder," a self-taught genius. The world of fashion, ever eager for a new sensation, was attracted ; the carriages of the wealthy blocked the street in which the painter resided, and for a time he reaped a rich harvest by his portraits. But soon the fickle tide of popularity flowed past him, and the painter was left neglected. He now applied himself with redoubled diligence to correcting the defects which marred his art, meriting the praise of his rival Northcote " Other artists paint to live ; Opie lives to paint." At the same time he sought to supplement his early education by the study of Latin and French and of the best English classics, and to polish the rudeness of his provincial manners by mixing in cultivated and learned circles. In 1786 he exhibited his first important historical subject, the Assassination of James I., and in the follow ing year the Murder of Rizzio, a work whose merit was recognized by the artist s immediate election as associate of the Academy, of which he became a full member in 1788. He was employed on five subjects for Boydell s "Shakespeare Gallery"; and until his death, on the 9th of April 1807, his practice alternated between portraiture and historical work. His productions are distinguished by breadth of handling and a certain rude vigour, individu ality, and freshness. They are wanting in grace, elegance, and poetic feeling. Opie is also favourably known as a Avriter on art by his Life of Reynolds in Wolcot s edition of Pilkington, his Letter on the Cultivation of the Fine Arts in England, in which he advocated the formation of a national gallery, and his Lectures as professor of painting to the Royal Academy, Avhich Avere published in 1809, with a memoir of the artist by his Avidow. OPITZ, MARTIN. See GERMANY, vol. x. p. 530. OPIUM (OTTIOV, dim. from OTTOS, juice), a narcotic drug prepared from the juice of, the opium poppy, Papaver som- niferum, L., a plant probably indigenous in the south of Europe and Avestern Asia, but now so Avidely cultivated that its original habitat is uncertain. The medicinal pro perties of the juice have been recognized from a very early period. It Avas known to Theophrastus by the name of P/KWVIOV, and appears in his time to have consisted of an extract of the Avhole plant, since Dioscori- des about 77 A.D. draAVS a distinction between yu.?yKwi etoi / , which he describes as an extract of the en tire herb, and the more active OTTOS, de rived from the cap sules alone. From the 1st to the 12th century the opium of Asia Minor appears to have been the only kind knoAvn in commerce. In the 13th century opium thebaicum is mentioned by Simon Januensis, physician to Pope Nicholas IV., Avhile meconium Avas still in use. In the 16th century opium is mentioned by Pyres (1516) as a production of the kingdom of Cous (Kuch Behar, south-Avest of Bhutan) in Bengal and of Mahva. 1 Its introduction into India appears to have been connected Avith the spread of Islam. The opium monopoly Avas the property of the Great 1 Aromatum Historia, ed. Clusius, Ant., 1574. _ 0piumPoppy(Paj , a , er , omni/eruTO) L .).