Calculations
Before 1824: Earliest methods of calculations
To surveyors and cartographers arithmetical calculations are absolutely necessary for the production of maps and plans. Calculations became a monotonous mental drudgery and from the earliest times mathematicians tried to invent instruments and tables which could minimise their work.
The earliest form of a mathematical calculator was the abacus, developed in Babylonia in about 3000 BC.
Both Hindu and Arab scholars continued to explore the mathematical process influencing European scholars like John Napier. In 1614, he introduced logarithmic tables whereby multiplication was reduced to addition and division to subtraction.
During the same period, men like Wilhelm Schick (1623) and Blaise Pascal (1644) built the first mechanical calculators.
1881 to 1900: The surveyor's calculations
By the 1890s, mechanical calculators were being used by Queensland surveyors and cartographers, but the size and weight of the machine limited their use to the office. Instead a set of chambers log tables was always found in every surveyors' field bag.
Field (at front) and office Arithmometers
1950 to 1985: A clever mechanical calculator
In the 1960s, Contina Ltd of Lichtenstein produced a miniature mechanical calculator called the 'Curta'. It was a clever and compact version of Thomas de Colmars 'Arithmometer', invented in 1820. Every Queensland surveyor immediately attached one of these to his belt for use in the field.
There were two models available. One provided 11 digit results and the other a more precise 15 digit output.
The Curta continued to be manufactured until about 1972. This was when the new electronic pocket calculators became available on the market. The Curta could not compete with the new technology.
The pioneer calculator, Hewlett Packard 35, replaced both the Curta and log tables as the means for calculations by surveyors and cartographers.
1985 to the Present: Automated calculations
Today, calculations are automated within software loaded on desktop computers, portable laptops or handheld GPS units.
Handheld GPS unit
Last updated: 17 June 2009