He completed some important public works, which, though, not numerous, were very useful. The principal were an aqueduct, which had been begun by Caius; an emissary for the discharge of the waters of the Fucine lake, The Fucine Lake is now called Lago di Celano, in the Farther Abruzzi. It is very extensive, but shallow, so that the difficulty of constructing the Claudian emissary, can scarcely be compared to that encountered in a similar work for lowering the level of the waters in the Alban lake, completed A. U. C. 359. and the harbour of Ostia; although he knew that Augustus had refused to comply with the repeated application of the Marsians for one of these; and that the other had been several times intended by Julius Caesar, but as often abandoned on account of the difficulty of its execution. He brought to the city the cool and plentiful springs of the Claudian water, one of which is called Caeruleus. and the other Curtius and Albudinus, as likewise the river of the New Anio, in a stone canal: and distributed them into many magnificent reservoirs. The canal from the Fucine lake was undertaken as much for the sake of profit, as for the honour of the enterprise; for there were parties who offered to drain it at their own expense, on condition of their having a grant of the land laid dry. With great difficulty he completed a canal three miles in length, partly by cutting through, and partly by tunnelling, a mountain; thirty thousand men being constantly employed in the work for eleven years.Respecting the Claudian aqueduct, see CALIGULA, c. xxi. He formed the harbour at Ostia, by carrying out circular piers on the right and on the left, with a mole protecting, in deep water, the entrance of the port.Ostia is referred to in a note, TIBERIUS, c. xi. To secure the foundation of this mole, he sunk the vessel in which the great obeliskSuetonius calls this " the great obelisk " in comparison with those which Augustus had placed in the Circus Maximus and Campus Martius. The one here mentioned was erected by Caligula in his Circus, afterwards called the Circus of Nero. It stood at Heliopolis, having been dedicated to the sun, as Herodotus informs us, by Phero, son of Sesostris, in acknowledgment of his recovery from blindness. It was removed by Pope Sixtus V. in 1586, under the celebrated architect, Fontana, to the centre of the area before St. Peter's, in the Vatican, not far from its former position. This obelisk is a solid piece of red granite, without hieroglyphics, and, with the pedestal and ornaments at the top, is 182 feet high. The height of the obelisk itself is 113 palms, or 84 feet. had been brought from Egypt;Pliny relates some curious particulars of this ship:-"A fir tree of prodigious size was used in the vessel which, by the command of Caligula, brought the obelisk from Egypt, which stands in the Vatican Circus, and four blocks of the same sort of stone to support it. Nothing certainly ever appeared on the sea more astonishing than this vessel; 120,000 bushels of lentiles served for its ballast; the length of it nearly equalled all the left side of the port of Ostia; for it was sent there by the emperor Claudius. The thickness of the tree was as much as four men could embrace with their arms."-B. xvi. c. 76. and built upon piles a very lofty tower, in imitation of the Pharos at Alexandria, on which lights were burnt to direct mariners in the night.