HIPPOCRENE (the "fountain of the horse," [Greek: he hippou krene]), the spring on Mt Helicon, in Boeotia, which, like the other spring there, Aganippe, was sacred to the Muses and Apollo, and hence taken as the source of poetic inspiration. The spring, surrounded by an ancient wall, is now known as _Kryopegadi_ or the cold spring. According to the legend, it was produced by the stamping of the hoof of Bellerophon's horse Pegasus. The same story accounts for the Hippocrene in Troezen and the spring Peirene at Corinth. HIPPODAMUS, of Miletus, a Greek architect of the 5th century B.C. It was he who introduced order and regularity into the planning of cities, in place of the previous intricacy and confusion. For Pericles he planned the arrangement of the harbour-town Peiraeus at Athens. When the Athenians founded Thurii in Italy he accompanied the colony as architect, and afterwards, in 408 B.C., he superintended the building of the new city of Rhodes. His schemes consisted of series of broad, straight streets, cutting one another at right angles. HIPPODROME (Gr. [Greek: hippodromos], from [Greek: hippos], horse, and [Greek: dromos], racecourse), the course provided by the Greeks for horse and chariot racing; it corresponded to the Roman _circus_, except that in the latter only four chariots ran at a time, whereas ten or more contended in the Greek games, so that the width was far greater, being about 400 ft., the course being 600 to 700 ft. long. The Greek hippodrome was usually set out on the slope of a hill, and the ground taken from one side served to form the embankment on the other side. One end of the hippodrome was semicircular, and the other end square with an extensive portico, in front of which, at a lower level, were the stalls for the horses and chariots. The modern hippodrome is more for equestrian and other displays than for horse racing. The Hippodrome in Paris somewhat resembles the Roman amphitheatre, being open in the centre to the sky, with seats round on rising levels.