ound the sun, and at different distances,
the chief of them eight in number, two of them, viz., Mercury and Venus,
revolving in orbits _interior_ to that of the earth, and five of them,
viz., Mars, Jupiter, Saturn, Uranus, and Neptune, _exterior_, the whole
with the PLANETOIDS (q. v.) and comets constituting the solar
system.

PLANTAGENETS, the name attached to a dynasty of kings of England,
who reigned from the extinction of the Norman line to the accession of
the Tudor, that is, from the beginning of Henry II.'s reign in 1154 to
the end of Richard III.'s on Bosworth Field in 1458. The name was adopted
by Geoffrey of Anjou, the husband of Matilda, the daughter of Henry I.,
whose badge was a sprig of broom (which the name denotes), and which he
wore in his bonnet as descended from the Earl of Anjou, who was by way of
penance scourged with twigs of it at Jerusalem.

PLANTIN, CHRISTOPHE, a printer of Antwerp, born near Tours, in
France; celebrated for the beauty and accuracy of the work that issued
from his press, the most notable being the "Antwerp Polyglot"; he had
printing establishments in Leyden and Paris, as well as Antwerp, all
these conducted by sons-in-law (1514-1589).

PLASSEY, a great battlefield in Bengal, now swept away by changes in
the course of the river, scarcely 100 m. N. of Calcutta; was the scene of
Clive's victory in 1757 with 800 Europeans and 2200 unreliable native
troops over Suraj-ud-Dowlah, the ruler of Bengal, which laid that
province at the feet of Britain, and led to the foundation of the British
Empire in India.

PLASTER OF PARIS, a compound of lime, sand, and water used for
coating walls, taking casts, and forming moulds.

PLATAEA, a city of ancient Greece, in western Boeotia, neighbour and
ally of Athens, suffered greatly in the Persian and Peloponnesian Wars.
It was destroyed by the Persians 480 B.C., by the Peloponnesian forces
429 B.C., and again by the Thebans 387 B.C. Philip of Macedon restored
the exiles to their homes in 338 B.C.

PLATO, the great philosopher, born in Athens, of noble birth, the
year Pericles died, and the second of the Peloponnesian War; at 20 became
a disciple of Socrates, and passed eight years in his society; at 30,
after the death of Socrates, quitted Athens, and took up his abode at
Megara; from Megara he travelled to Cyrene, Egypt, Magna Graecia, and
Sicily, prolonging his stay in Magna Graecia, and studying under
Pythagoras, whose philosoph