nce in the NE.; on its shores stand
Hamilton, Toronto, and Kingston on the N., and Oswego on the S.; canals
connect it with Lake Erie and the Hudson River, and it is a busy and
always open highway of commerce.

ONTOLOGY, another name for METAPHYSICS (q. v.) or the
science of pure being, being at its living source in spirit or God, or
Nature viewed as divine, especially as the ground of the spiritual in man
and giving substantive being to him.

ONYX, a variety of agate or chalcedony, in which occur even layers
of white and black or white and brown, sharply defined in good specimens;
they come from India, and are highly valued for cameo-cutting.

OOSTERZEE, JAN JAKOB VAN, a theologian of the Dutch Church, born at
Rotterdam; became professor at Utrecht, wrote several theological and
exegetical works on evangelical lines (1817-1882).

OPAL, a variety of quartz, of which the finest kind, precious opal,
is translucent, with blue or yellow tint, and when polished with a convex
surface shows an admirable play of colours; it is found chiefly at
Cerwenitza, Austria.

OPEN SECRET, THE, the secret that lies open to all, but is seen into
and understood by only few, applied especially to the mystery of the
life, the spiritual life, which is the possession of all.

OPEN, SESAME, the magic formula the pronunciation of which opened
the robbers' stronghold in the "Arabian Nights."

OPERA, a drama set to music and acted and sung to the accompaniment
of a full orchestra, of which there are several kinds according as they
are grave, comic, or romantic.

OPERA BOUFFE, an opera in an extravagant burlesque style, with
characters, music, and other accompaniments to match; is the creation of
OFFENBACH (q. v.), his more distinguished successors in the
production of which have been Lecocq, Herve, and Strauss.

OPHELIA, the daughter of Polonius in "Hamlet" and in love with the
lord, but whose heart, from the succession of shocks it receives, is
shattered and broken.

OPHICLEIDE, a keyed brass wind instrument of recent invention, of
great compass and power, and of which there are two kinds in use.

OPHIR, a region in the East of uncertain situation, frequently
referred to in Scripture as a region from which gold and precious stones
were imported.

OPHITES, a sect of Gnostics who regarded the serpent as a benefactor
of the race in having persuaded Eve to eat of the tree of the _knowledge_
of good and evil in dis