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1968 Australia Twenty Dollars Paper - XBT
Has a strong centrefold and top right hand corner is also dog eared.
Otherwise a nice example with good colour and very light soiling.
A rare year and highly valuable series.
Hargrave had been interested in experiments of all kinds from an early age, particularly those with aircraft. When his father died in 1885, and Hargrave came into his inheritance, he resigned from the observatory to concentrate on full-time research. and for a time gave particular attention to the flight of birds. He chose to live and experiment with his flying machines in Stanwell Park, a place which offers excellent wind and hang conditions and nowadays is the most famous hang gliding and paragliding venue in Australia.
In his career, Hargrave invented many devices, but never applied for a patent on any of them. He needed the money but he was a passionate believer in scientific communication as a key to furthering progress. As he wrote in 1893:
"Workers must root out the idea that by keeping the results of their labors to themselves, a fortune will be assured to them. Patent fees are much wasted money. The flying machine of the future will not be born fully fledged and capable of a flight for 1000 miles or so. Like everything else it must be evolved gradually. The first difficulty is to get a thing that will fly at all. When this is made, a full description should be published as an aid to others. Excellence of design and workmanship will always defy competition."
Among many, three of Hargrave's inventions were particularly significant:
Study of curved aerofoils, particularly designs with a thicker leading edge.
The box kite (1893), which greatly improved the lift to drag ratio of early gliders.
Work on the rotary engine, which powered many early aircraft up until about 1920.
Hargrave lifted sixteen feet from the ground by a tandem of his box kites.
He made endless experiments and numerous models, and communicated his conclusions in a series of papers to the Royal Society of New South Wales. Two papers which will be found in the 1885 volume of its Journal and Proceedings show that he was early on the road to success. Other important papers will be found in the 1893 and 1895 volumes which reported on his experiments with flying-machine motors and cellular kites.
*All biographical details are taken from Wikipedia for education purposes only
Obverse: Sir Charles Edward Kingsford Smith MC, AFC (9 February 1897 – 8 November 1935), often called Charles Kingsford Smith, or by his nickname Smithy, was a well-known early Australian aviator. In 1928, he made the first trans-Pacific flight from the United States to Australia. He also made the first non-stop crossing of the Australian mainland, the first flights between Australia and New Zealand, and the first eastward Pacific crossing from Australia to the United States. He also made a flight from Australia to London, and set a new record of 10.5 days.
Reverse:Lawrence Hargrave (29 January 1850 – 14 July 1915) was an engineer, explorer, astronomer, inventor and aeronautical pioneer.
Watermark: Captain Cook in left panel