Chain standardisation
1881 to 1900: Establishing standards for comparisons
The act of surveying requires distances to be measured with a high degree of precision. In order for surveyors to achieve this, their chains or tapes would be compared against an accurate standard.
In 1883 W.A. Tully, the Surveyor General received from his counterpart in New South Wales, P.F.B. Adams, a standard steel bar to calibrate the tapes. These tapes were used to measure a base line on the Prairie Plain (Jondaryan). Tully, in his annual report for 1883, described the octagonal bar:
In order to establish a reliable unit of measurement, I obtained from the Survey Department of New South Wales, a standard steel bar floating in mercury ten feet in length, and also an apparatus with micrometer microscopes attached, by which a steel tape of any length could be measured off direct from the bar. Tully WA 1883
Tape standard testing in the Lands Office, 1890
This apparatus was designed by Mr Adams, Surveyor General of New South Wales, and was constructed under the superintendence of Mr Russell, the government astronomer of that colony.
In August 1883, the Surveyor General sought approval from the Crown Law Office to erect a standard of 66 and 100 feet in length. This was placed on three sandstone blocks along the North Quay frontage of the Supreme Court Building, Brisbane.
In 1885, the Chief Justice’s associate, J. Harrison Byrne, wrote to the Surveyor General asking that the surveyors cease using this standard because its use:
has begun to destroy his quiet and privacy which it was originally intended his chambers should have. Byrne JH 1885
As a result, the base standard was only used about a dozen times.
A chain standard in the Old Supreme Court grounds, North Quay, Brisbane
In November 1884, a new base for calibrating surveyors' tapes was laid down on the cement floor of the new survey office verandah in George Street (on the site of the present Supreme Court).'Queensland Institute of Surveyors Transactions and Proceedings', 9th April 1901, vol1 p18, Museum of Lands Mapping and Surveying, Brisbane
Silver discs let into round copper plugs were placed in the concrete floor at intervals of 30, 66, 100 and 110 feet. The problem with this base was the difficulty in determining the correct temperature of tapes resting flat on a concrete floor.
In 1896, Rockhampton District Surveyor C.T. Bedford established a standard of 500 links. This incorporated a 50 and 100 link and a 100 feet standard in Fitzroy Square.Morning Bulletin 28th March 1896, Rockhampton The site and materials used to construct the base were donated by the Rockhampton Council. The base was marked by eleven concrete piers, fifty links apart and two and a half feet high. Bedford required the chain to be off the ground to record a true temperature of the chain:
When a standard was laid on the ground, the thermometer registered the heat of the ground and not necessarily the heat of the chain. By building piers, the chain when tested would be suspended in the atmosphere. Then by suspending the thermometer from a tripod placed close to the chain, a reading would be obtained which would accurately show the temperature of the chain - the thermometer and chain being suspended in the atmosphere under identical conditions.Morning Bulletin 28th March 1896, Rockhampton
By the 1890s, the Gunter's Chain was replaced by the five chain band. In 1899, a base line comparator 5 chains in length was installed in the Brisbane Botanic Gardens. This allowed for tapes longer than 110 feet in length to be compared with each other.'Manuscript SUR/A99/1478' 1899, Qld State Archives, Brisbane
Base line comparator in the Brisbane Botanic Gardens, 1899
1901 to 1920: Possible early decimilisation
In 1903, a new standard bar ordered from Troughton and Simms, London, arrived in Queensland.Survey Office Annual Report 1903, p81, Brisbane
At the time, Great Britain and its dependencies were considering the adoption of a decimal system of weights and measures.
There were one, two and three metre lengths marked on the ten foot bar which was already marked every three feet.
This bar was never used due to a suitable site not being found for its installation. It is presently stored in the Queensland Museum of Lands Mapping and Surveying.
In 1910, metal plugs at 66 (100lks) and 82.5 (125 lks) foot intervals were inserted in the concrete walkway on the north western side of the courtyard of the Executive Building (now the Casino Hotel). This base was destroyed when the building was refurbished for the hotel in 1985.
1921 to 1950: A standard reference constructed in Brisbane
In 1932, the Surveyor General of Queensland had a standard constructed in Stephens Lane on the south-eastern side of the Lands Administration Building, George Street, Brisbane.'Manuscript file19 part1' 1932, Qld State Archives, Brisbane
The base consisted of three concrete pillars with a wooden rail in between. Metal plugs were inserted into the tops of the pillars at intervals of 00, 66 and 100 feet distances. In 1940, an extra pillar at 50 feet was installed.
In 1950 Bill Newell, the officer in charge of tape standardisation reported on the problems he experienced while calibrating surveyors chains:
Besides being open to vandals, it must be admitted the site is not altogether satisfactory, one very serious drawback being the exposure to rain and sun rendering work impossible except in dry weather and afternoons.
Though the Weights and Measures Department have not mentioned the following unpleasant conditions under which one sometimes has to work, a means of protecting employees from lighted cigarette butts, hot tea, or cold water thrown from the windows above should be considered. Although fortunately only minor burns have so far been inflicted, nevertheless the lodging of a lighted cigarette butt in one's hair or clothing might have more serious consequences. Furthermore, the smells from the drains in the vicinity at times are almost overpowering.Qld State Archives
1951 to 1985: Surveyor's Current Tape Reference
In 1964, a new tape calibration bench was installed inside the Weights and Measures departmental building, Morcom House, George Street, Brisbane.
Last updated: 17 June 2009