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Parallel ruler owned by W Pudsey Dawson, Royal Navy
Parallel ruler owned by W Pudsey Dawson, Royal Navy

Parallel ruler owned by W Pudsey Dawson, Royal Navy

Date1875-1910
Object number00056608
NameParallel ruler
MediumWood with brass fittings
DimensionsOverall (Dimensions of ruler when closed): 152 x 35 x 3 mm, 30 g
ClassificationsTools and equipment
Credit LineAustralian National Maritime Museum Gift from Leslie Roberts
DescriptionWilloughby Pudsey Dawson (30 January 1862 – 4 September 1936) was a Royal Navy officer whose legacy includes an exquisite series of maritime charts of the Australasian region. He served on numerous naval vessels, including HMS WOLVERENE, DART and EGERIA, before taking command of HMS WATERWITCH, PENGUIN and TRITON. Over 1900-05, Captain Dawson led an extensive hydrographic and cartographic survey of the Pacific Ocean and New Zealand coast as master of HMS PENGUIN on the Australia Station. This pair of parallel rulers engraved with Dawson’s name may have been taken on those voyages. They would have allowed him to plot precise parallels of latitude, line of position, a compass bearing or determine true course. As fundamental navigational instruments associated with a master cartographer, this set of rulers contributed to an expanding, accurate and enduring record of the seas and coastlines across the Australasian region.HistoryWilloughby Pudsey Dawson (30 January 1862 – 4 September 1936) was a British naval officer who undertook extensive survey work in Australia, the Pacific and Britain. He is noted for his cartographic and photographic talents. Dawson was promoted to Lieutenant on 30 June 1884, Commander on 31 December 1898, Captain on 31 December 1904 and Rear-Admiral on the retired list, 3 June 1916. His commands included HMS WATERWITCH (1897–1900), HMS PENGUIN (1902–05) and HMS TRITON (1906–09). Born in Staffordshire into a seafaring family, Dawson joined the Royal Navy (RN) at the age of 13. As a 14-year-old he voyaged to Sydney aboard HMS WOLVERENE, which became the flagship of the Australia Station upon its arrival in 1876. Dawson served aboard HMS DART from 1882, undertaking survey work around the Pacific, which was likely where he developed his hydrographic and cartographic skills. From early in his career, Dawson also became an avid photographer, with hundreds of his images surviving. In the 1890s Dawson was posted to HMS EGERIA on the Royal Navy’s China Station, before taking command of WATERWITCH, which surveyed the coast of China in the years prior to the Boxer rebellion. Returning to Australia to command PENGUIN, Dawson led an extensive surveying program throughout the Pacific, which included charting its deepest known point at that time. PENGUIN rescued the survivors of the shipwreck ELINGAMITE in 1902. Charts produced under his leadership during this period are considered by collectors to be works of art, especially the New Zealand series. These include Mayor Island to Poverty Bay (published 1902), Omaha Bay to Tiri-Tiri Matangi (1905), Great Barrier Island (1905), Bream Head to Tepaki Point (1906), Maunganui Bluff to Manukau Harbour and Tutukaka Harbour (1908). After returning to the UK and his next command, HMS TRITON, Dawson produced a chart of Cookham Short and Gillingham on the Kent coast (1906). He resigned from the RN in February 1910 and became Chief Marine Surveyor to the Port of London, finally retiring in 1926 at the age of 64. Having married Charlotte Cope in 1887 during his first period in Australia, the couple had five children who were variously born in New South Wales and the UK. After retiring, Dawson returned to Australia to be with his daughter Dorothy, dying in Edgecliff aged 75. He is buried at St Thomas’s Rest Park, North Sydney. Parallel rulers (or rules) were invented in the 16th Century but were not widely adopted until the 18th Century. The double pivots ensure that the two elements remain parallel at all times, allowing an angle to be transferred accurately from one location on a chart to another. They can be used to ensure precise parallels to meridians of longitude or parallels of latitude, which are essential to accurate location. They can also be used to plot a line of position, find a compass bearing or determine true course, allowing exact calculation of distance travelled or remaining. As fundamental nautical plotting tools, this pair of rulers would have likely have been early purchases by Dawson and may have been integral to his navigation and charting work.SignificanceAccurate navigation, hydrography and cartography were central to safe and efficient sailing in the nineteenth century. Building upon tools and techniques developed since the sixteenth century, simple devices such as these parallel rulers allowed for consistent determination of position, course and speed. They also assisted in the accurate plotting of ocean depths and coastal features. These parallel rulers might be commonplace apart from their association with Willoughby Pudsey Dawson, a Midshipman who rose to become Rear-Admiral in the Royal Navy during a career that spanned 1875 to 1910. During that time, Dawson undertook hydrographic and cartographic survey work in China, Australia, New Zealand, the Pacific Ocean and England. His legacy, linked directly to these rulers, is a series of navigational charts that are considered works of art and guided mariners for decades after their creation.