Gunter Survey Chain circa 1860 Iron, brass Gift of the Parks & Wildlife Commission of the Northern Territory - 2010 TH2011/0058

The measurement of land has had an interesting history over time. Innumerable techniques, instruments, and measurement standards have been developed through the ages to survey land for commercial and legal purposes, most of which were confusing or relatively inaccurate. However, in 1620 the English clergyman Edmund Gunter developed a system that would simplify and standardise land measurement. He divided a furlong (660 feet or 201.168 metres) into 10 equal parts which he called chains (66 feet or 20.1168 metres), and divided each chain into 100 links (7.92 inches or 201.168 mm). He then constructed an actual chain made of iron that could be physically used to measure land using these units.

This became known as the Gunter chain and it revolutionised surveying. Each chain was made up of 100 iron links connected by three oval rings. Each end was furnished with a swivelling brass handle, and at every tenth link a brass tally marker was attached that had one, two, three or four notches that marked ten, twenty, thirty, or forty links from either end. The fiftieth link had a rounded tally and indicated the middle of the chain. These tallies allowed the chainman to easily count links along the chain as he surveyed.

Gunter chains became the mainstay of surveying from the mid 1600s to the late 1800s, when flat steel tapes were introduced which were stronger and even more accurate than the chain.

This particular Gunter chain was made by the firm James Chesterman and Co. of Sheffield in England who were renowned for making fine measuring instruments.

What makes this chain so special is that it was owned and used by Gilbert Rotherdale McMinn during his time in the Territory. He was one of the many surveyors that came to Port Darwin with the 1869 Northern Territory Survey Expedition led by Surveyor-General George Goyder. They surveyed four townships (Palmerston –now Darwin, Virginia, Southport and Daly) and the hinterland as far inland as the Finniss and Adelaide Rivers. They arrived on the 5 February 1869 and within eight months had surveyed over 660,000 acres of land – a Herculean achievement. McMinn was in charge of No.4 Survey Party.

In 1871 McMinn took charge of surveying the central sections (south of Alice Springs) of the Overland Telegraph Line, and was the first European to see Simpson’s Gap. He assisted in the construction of the Alice Springs Telegraph Station, and in 1873 was appointed Senior Surveyor in the Northern Territory. He also took on the role of Acting Government Resident for 14 months prior to the arrival of J.L. Parsons. He left the Territory in 1888 and lived out the remainder of his life in Melbourne.

His legacy lives on with a number of streets, a lagoon, and other geographical features named in his honour.

This object is part of the MAGNT permanent collection. It is not currently on display.