Cape Don Light
Cape Don Light is an active lighthouse located on Cape Don, at the tip of the Cobourg Peninsula, Northern Territory, Australia, in Garig Gunak Barlu National Park, marking the entrance to the Dundas Strait. It is Australia's northernmost traditional lighthouse. The station served on the important route to Darwin, between the peninsula and Melville Island. The tower was constructed in 1915–1917, during the "Golden Age of Australian Lighthouses" (1913–1920), and the tower was manned until 1983. During the entire period that the tower was manned it also maintained meteorological records which were well placed to assist in cyclone development tracking. The complex consists of the lighthouse, three residences and ancillary buildings. Cape Don was named by Phillip Parker King in 1818, as a compliment to General Sir George Don, the Lieutenant-Governor of Gibraltar. History The Northern Territory was transferred from the government of South Australia to the federal parliament in 1911. The Commonwealth Lighthouse Service was officially formed on 1 July 1915, and one of the first actions of the service was to realise the need for a lighthouse on the Cobourg Peninsula, as the passage between the peninsula and Melville Island was an important route to Darwin. Construction of the tower was the largest project undertaken by the Commonwealth Lighthouse Service during the "Golden Age of Australian Lighthouses" (1913–1920). Work on the tower began in May 1915. An iron structure was deemed unsuitable due to the tropical conditions, and the local ironstone was not suitable for concrete, so materials had to be shipped from Melbourne. However, landing conditions at the site meant the closest location for landing the materials was about to the east, at Christies Bay. A jetty and a tramway were constructed, and the materials were drawn by horses from the landing location. The climate and the grade meant only two round trips could be made each day, and in addition, construction could only be carried out on the dry season, from April to November. As a result, construction took three years, completing in June 1917. Though the lantern was installed and ready to be lit, an earthquake hit the tower in August 1917. Though the structure was not damaged, of mercury were lost from the mercury-bearing pedestal bath. The lighthouse was finally officially lit on 15 September 1917. The tower original light source was a 55-millimetre (2.2 in) vapourised kerosene incandescent mantle, with an intensity of 150,000 cd and a visible range of . The original lens was a Chance Brothers 3rd order 500-millimetre (20 in) dioptric fresnel lens. The apparatus was a rotating pedestal floating in a mercury bath, operated by a clockwork mechanism with descending weights, which only had to be rewound once every twelve hours. In the Second World War, a radar station was installed near the complex. In the early 1970s, the tower was electrified, with power coming from diesel generators. The light source was converted to a 120-volt tungsten-halogen lamp. In 1983 the light was automated and the station was demanned.