HIOUEN-THSANG, a Chinese Buddhist, who in the 7th century traversed India collecting books bearing upon the creed and law of Buddhism, and spent his time after his return in translating them.

HIPPARCHUS, ancient astronomer, born at Nicaea; flourished in the 2nd century B.C.; discovered among other things the precession of the equinoxes, determined the place of the equinox, and catalogued 1000 fixed stars.

HIPPIAS, tyrant of Athens, son of Pisistratus; expelled from Athens, applied to the Persians to reinstate him, and kindled the first Persian War with Greece; fell at Marathon, 490 B.C.

HIPPOCRATES, the father of medicine, born at Cos, 460 B.C.; was a contemporary of Socrates and Plato; was of wide-spread renown as a physician; settled in Thessaly and died at Larissa advanced in years; no fewer than 60 writings are ascribed to him, but only a few are genuine.

HIPPOCRENE (lit. the fountain of the horse), a fountain on Mount Helicon, in Boeotia, sacred to the Muses, and said to have been caused by PEGASUS (q. v.) striking the spot with his hoof.

HIPPODAMI`A, in the legendary lore of Greece, was the beautiful daughter of Oenomaus, king of Pisa, in Elis, and the pleiad Sterope; the oracle had foretold death to Oenomaus on the occasion of his daughter’s marriage, to prevent which the king had made it a condition that each suitor should run a chariot race with him, and that, if defeated, should be put to death; many had perished in the attempt to beat the king, till Pelops, by bribing Oenomaus’s charioteer, won the race; the king in a frenzy killed himself, and the kingdom and the fair Hippodamia passed to Pelops.

HIPPOLYTE, queen of the Amazons, slain by Hercules in order to obtain and carry off her magic girdle.

HIPPOLYTUS, ST., bishop of Portus, near Rome; lived in the 3rd century B.C.; a lost work of his, “A Refutation of all the Heresies,” was discovered at Mount Athos in 1842, his authorship of which Bunsen vindicated in “Hippolytus and his Age.”

HISPANIA, the ancient name of Spain and Portugal among the Latins.

HISSAR, 1, a district (776) in the Punjab, India; for the most part sandy, yet in rainy years produces good crops of rice, barley, &c., and is noted for its white cattle; the capital (14), bearing the same name, is situated on the Western Jumna Canal, 102 m.  W. of Delhi. 2, Also a district in Central Asia, a dependency of the Khan of Bokhara lying N. of the Oxus River, and separated from Bokhara by a branch of the Thian Shan Mountains; has a fertile soil, and exports corn, sheep, &c., to Bokhara.

HISTOLOGY, the science of tissues, vegetable and animal.

HITCHCOCK, EDWARD, American geologist, born in Massachusetts; reported on the geology of his native State, and on the agricultural schools of Europe; wrote “Elementary Geology” and the “Religion of Geology” (1793-1864).

HITCHIN (9), a very old and still prosperous town of Hertfordshire, on the Hiz, 14 m.  NW. of Hertford; does a flourishing trade in corn, malt, and flour; brewing and straw-plaiting are important industries, and it has long been noted for its lavender and lavender water.