South Australia–Victoria border dispute
The border between the Australian state of South Australia and what is today the State of Victoria was established in 1836 by imperial letters patent "as the 141st degree meridian of longitude east of Greenwich". In 1836 the land we now call Victoria was part of the colony of New South Wales, so the original Victorian border was actually drawn between the colonies of South Australia and New South Wales. Due to human error by numerous explorers and surveyors, it took more than 75 years and a protracted legal dispute before the precise placement of the border was settled, resulting in the forfeiture of more than 1,300 km2 (500 sq mi) of territory from South Australia to Victoria.
Following the establishment of the colony of South Australia in 1835, the region between the coast and the Murray River was rapidly being settled by squatters selecting large runs for sheep grazing. With no clear border legal oversight was impossible. An accurate border needed to be defined. The earliest relevant reference to the eastern boundary of South Australia is contained in a despatch dated 30 September 1844 from Governor Grey of that Colony to Lord Stanley. The Governor reminded the Secretary of State that it would be extremely difficult to determine with accuracy a number of points upon the earth's surface through which the 141st degree of East longitude passes, and pointed out that in addition to difficulty there would be attendant expense both in ascertainment and maintenance.
In 1839 Charles Tyers was transferred from the Royal Navy to the Colonial Service and instructed by Sir George Gipps, the Governor of New South Wales, to ascertain the precise longitude at the mouth of the Glenelg River so that a distance to the 141st meridian (the eastern border of South Australia) could be measured.
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