ring the Revolution
period.

OELAND (37), an island off the SE. coast of Sweden, 55 m. long and
about 10 m. broad; has good pasture ground, and yields alum; the
fisheries good.

OENONE, 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
Helene," "Orphee 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 territ