name of Millers Point remembers this early land use. In 1803, Fort Philip was built on the site under the direction of Governor Hunter to defend the new settlement against a possible attack by the French and also from rebellious convicts. The fort was never required to be used for any such purposes. In 1825 the eastern wall of the fort was converted to a signal station. Flags were used to send messages to ships in the harbour and to the signal station on the South Head of the harbour. The site was known as Flagstaff Hill during and after the Macquarie era. A flagstaff had been erected on the site by 1811. Flag signalling was a cumbersome process and Commissioner Bigge advised Macquarie that it was expedient to erect a semaphore at South Head and Fort Phillip. The flag and semaphore were used for signalling in a variety of combinations. Observatory An early observatory was established in 1788 by William Dawes on Dawes Point, at the foot of Observatory Hill, in an ultimately unsuccessful attempt to observe in 1790 the return of a comet suggested by Edmond Halley (not Halley's Comet but a different one). In 1848, a new signal station was built by the Colonial Architect, Mortimer Lewis, on top of the fort wall on Windmill Hill. At the instigation of the Governor, Sir William Denison, it was agreed seven years later to build a full observatory next to the signal station. The first Government Astronomer, William Scott, was appointed in 1856, and work on the new observatory was completed in 1858. The most important role of the observatory was to provide time through the time-ball tower. Every day at exactly 1.00 pm, the time-ball on top of the tower would drop to signal the correct time to the city and harbour below. At the same time a cannon on Dawes Point was fired, later the cannon was moved to Fort Denison. The first time-ball was dropped at noon on 5 June 1858. Soon after the drop was rescheduled to one o'clock. The time-ball is still dropped daily at 1pm using the original mechanism, but with the aid of an electric motor, not as in the early days when the ball was raised manually. After the federation of Australia in 1901, meteorology became a function for the Commonwealth Government from 1908, while the observatory continued its astronomical role.