his court
and kept him in his service five years, after which he returned to
Florence and executed his famous bronze "Perseus with the Head of
Medusa," which occupied him four years; was a man of a quarrelsome
temper, which involved him in no end of scrapes with sword as well as
tongue; left an autobiography, from its self-dissection of the deepest
interest to all students of human nature (1500-1571).

CELSIUS, a distinguished Swedish astronomer, born at Upsala, and
professor of Astronomy there; inventor of the Centigrade thermometer
(1701-1744).

CELSUS, a celebrated Roman physician of the age of Augustus, and
perhaps later; famed as the author of "De Medicina," a work often
referred to, and valuable as one of the sources of our knowledge of the
medicine of the ancients.

CELSUS, a philosopher of the 2nd century, and notable as the first
assailant on philosophic grounds of the Christian religion, particularly
as regards the power it claims to deliver from the evil that is inherent
in human nature, inseparable from it, and implanted in it not by God, but
some inferior being remote from Him; the book in which he attacked
Christianity is no longer extant, only quotations from it scattered over
the pages of the defence of Origen in reply.

CELTIBE`RI, an ancient Spanish race occupying the centre of the
peninsula, sprung from a blending of the aborigines and the Celts, who
invaded the country; a brave race, divided into four tribes;
distinguished in war both as cavalry and infantry, and whom the Romans
had much trouble in subduing.

CELTS. The W. of Europe was in prehistoric times subjected to two
invasions of Aryan tribes, all of whom are now referred to as Celts. The
earlier invaders were Goidels or Gaels; they conquered the Ivernian and
Iberian peoples of ancient Gaul, Britain, and Ireland; their successors,
the Brythons or Britons pouring from the E., drove them to the
westernmost borders of these countries, and there compelled them to make
common cause with the surviving Iberians in resistance; in the eastern
parts of the conquered territories they formed the bulk of the
population, in the W. they were in a dominant minority; study of
languages in the British Isles leads to the conclusion that the Irish,
Manx, and Scottish Celts belonged chiefly to the earlier immigration,
while the Welsh and Cornish represent the latter; the true Celtic type is
tall, red or fair, and blue-eyed, while the short, swarthy