In the centre is a fountain, with granite basin 26 feet in diameter,
which formerly stood in the Forum; also two beautiful colossal
horse-tamers in marble, supposed to be Castor and Pollux by some, by
others, Alexander and Bucephalus. The Latin inscriptions state one of
these colossi to be the work of Phidias, the other of Praxiteles. Both
were presented to Nero by Tiridates, king of Armenia. They once
ornamented the Baths of Constantine, and have never been buried. The
whole is surmounted by an Egyptian obelisk found near the Mausoleum of
Augustus. _On the left_ is the king's