Alexander Dalrymple (July 24, 1737 – June 19, 1808) was a
Scottish geographer and the first
Hydrographer of the
British Admiralty. He was the main proponent of the theory that there existed a vast undiscovered
continent in the
South Pacific,
Terra Australis Incognita. He produced thousands of nautical charts mapping a remarkable number of seas and oceans for the first time and contributing significantly to the safety of shipping. His theories prompted a number of expeditions in search of this mythical land, until
James Cook's second journey (1772–1775) led to the conclusion that, if it did exist, it was more southernly than the 65° line of latitude South.
Dalrymple was born at New Hailes, near
Edinburgh, the seventh of sixteen children of Sir James Dalrymple and his wife the daughter of the
Earl of Haddington. He went to
London in 1752 and was appointed a writer in the
British East India Company, being first posted to
Madras. While with the EIC he became interested in the possibilities of trade with the East Indies and China and subsequently negotiated a treaty with the sultan of
Sulu and visited
Canton at the age of only 22. In 1765 he returned to London where was elected a fellow of the
Royal Society. There he became acquainted with
John Smeaton, who during the course of his studies on windmills had devised a descriptive scale for grading wind speed. This scale was included in the paper for which he was awarded the
Copley Medal. In
Defining the Wind: The Beaufort Scale and How a 19th-Century Admiral Turned Science into Poetry author Scott Huler relates that Dalrymple's voyages had convinced him that a standard scale for measuring the speed of wind at sea would be of great value to sailors, and that he had included Smeaton's scale in his work
Practical Navigation, which was written around 1790 but never published. It is believed that Dalrymple conveyed this information to
Francis Beaufort who later refined the wind scale that bears his name and that is still in use today.
Whilst translating some Spanish documents captured in the
Philippines in 1752 Dalrymple had found
Luis Váez de Torres testimony proving a passage south of
New Guinea now known as
Torres Strait. This discovery led Dalrymple to publish the
Historical Collection of the Several Voyages and Discoveries in the South Pacific Ocean in 1770-1771 which aroused widespread interest in his claim of the existence of an unknown continent. This led Captain Cook to undertake another voyage into the South Pacific. He was bitterly disappointed that it was Captain Cook and not him who was appointed commander of the expedition which eventually led in 1770 to the British discovery and charting of the Eastern coastline of Australia.
In 1782 he was elected a foreign member of the
Royal Swedish Academy of Sciences.
See also
