[Oenonë], a nymph of Mount Ida, near Troy, beloved by and married to Paris, but whom he forsook for Helen; is the subject of one of Tennyson's poems.
[Oersted, Hans Christian], a Danish physicist; was professor of Physics in Copenhagen, the discoverer of electro-magnetism, of the compressibility of water, and the metal aluminium; did much to popularise science in a volume entitled "The Soul in Nature" (1777-1851).
[Oesel] (51), a marshy, well-wooded island at the mouth of the Gulf of Riga, in the Baltic, 45 m. long and 25 m. of average breadth; has some low hills and precipitous coasts; Arensburg (4), on the SE. shore, is the only town; Danish from 1559, the island passed to Sweden in 1645 and to Russia in 1721; the wealthier classes are of German descent.
[Offa's Dyke], an entrenchment and rampart between England and Wales, 100 m. long, extending from Flintshire as far as the mouth of the Wye; said to have been thrown up by Offa, king of Mercia, about the year 780, to confine the marauding Welsh within their own territory.
[Offenbach, Jacques], a musical composer, born at Cologne, of Jewish parents, creator of the opera bouffe; was the author of "La Belle Hélène," "Orphée aux Enfers," "La Grande Duchesse," "Madame Favart," &c. (1810-1880)
[Offertory], in the Roman Catholic Church a portion of the liturgy chanted at the commencement of the eucharistic service, also in the English the part of the service read during the collection of the alms at communion.
[Ofterdingen, Heinrich von], a famous [minnesinger] (q. v.) of the 15th century.
[Ogham] or Ogam, an alphabet of 20 letters in use among the ancient Irish and Celts, found carved on monumental stones in Ireland, Wales, Cornwall, and the North of Scotland.
[Oglethorpe, James Edward], English general, born in London; served in the Marlborough wars, sat in Parliament for several years, conceived the founding of a colony for debtors in prison, and founded Georgia; returning to England, fought against the Pretender, and died in Essex (1696-1785).
[Ogowe`], a West African river, 500 m. long, rises in the Akukuja plateau, and following a semicircular course northward and westward enters the Atlantic by a delta at Cape Lopez, its course lying wholly within French Congo territory; in the dry season its volume is much diminished, and its many sandbanks prevent its navigation except by small boats.