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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
A C Gregory Lunar Distance
From: Kieran Kelly
Date: 2003 Jul 28, 22:09 +1000
From: Kieran Kelly
Date: 2003 Jul 28, 22:09 +1000
I have recently completed a study of a lunar distance observation completed by the Australian explorer Augustus Charles Gregory in 1856. This paper was completed as a guide to the explorer's detailed records filed in the Mitchell Library in Sydney. Although it is 60 pages long I thought some members of the list may be interested in reading it as it is a practical demonstration of how lunar distance observations were undertaken in the field and the shortcuts and techniques used by professional surveyors and explorers to work out their longitude. All Gregory's lunar observations were reduced to longitude in the field , unlike those of his predecessors in the United States, Lewis and Clark. To visit the site the following URL should be used. Note that the entire address has to be typed including the spaces. http://users.bigpond.net.au/kjkelly/gregorylunar/A Lunar Distance Calculation v1.pdf Because of the length of the document and its size, it may not be practicable for some members to access. Gregory was Australia's most outstanding terrestrial explorer, on a par with James Cook, Matthew Flinders and Phillip Parker King. While Cook, Flinders and King delineated the exterior coastline of this country, so Gregory delivered us the interior. He invented the modern Australian horse packsaddle, a revolutionary compass known as the Gregory pattern compass, was a competent horologer able to strip and repair chronometers in the bush, worked out advanced methods of preserving food for long distance packhorse trips and was free of scurvy throughout his entire exploring career. During this career he did not lose one man and never shot an aborigine. I commend his work to you with the suggestion that exploration at this level was really a work of art. I welcome any feed back on this document either via the list or by email on kkelly@bigpond.net.au. The author acknowledges the contribution of list members George Bennett (Australia) George Huxtable (England) Bruce Stark (USA) for their assistance in the preparation of the material. Kieran Kelly