POWERHOUSE COLLECTION

Photograph of a telescope at Sydney Observatory

Object No. P3549-3

The telescope in this photograph was ordered from Troughton and Simms in 1875 arrived in Australia in 1877. It is one of the most significant of the museum's astronomical instruments and was used to measure Sydney time and do a large part of the observational work at Sydney Observatory. Upon its arrival it replaced the old transit telescope, which was thought to be deficient, and Russell used it to acquire accurate positions of stars for the trigonometrical survey of New South Wales. One of the new innovations included in its design was the casting of circle from solid metal circles rather than in parts or leaving areas open. This was done to ensure the effects of temperature were spread more evenly across the circles to decrease distortion. Russell believed this telescope was the first to be cast in this way by Troughton and Simms. The photograph is a rare original record of the transit telescope taken in situ at Sydney Observatory around 1900. It is of scientific significance for its relationship to the scientists and the instruments which are part of Australia's early scientific history. Geoff Barker, Assistant Curator, Total Asset Management Project, January 2008 References Todd, David, P., Stars and Telescopes, Sampson Low, Marston, and Co., 1900 Haynes, Raymond, Haynes, Roslynn, Malin, David, McGee, Richard, Explorers of the Southern Sky, Cambridge University Press, 1996 De-Clerq, P.R., Nineteenth Century Instruments and their Makers; Rodopi, Amsterdam, 1985 Russell, H., C., "Report of Astronomer for 1874 & 1875', New South Wales Government Printer, 1876 Russell, H.C., 'Scientific Notes', in Transactions and Proceedings of the Royal Society of New South Wales for the Year 1875, Volume. IX, Thomas Richards, Government Printer, Sydney, 1876