An ancient profession, surveying has evolved along with civilization to the extent that the world as we know it would not be the same without it. Though surveyors began with primitive tools such as rope to make land judgments, modern land professionals benefit from a wide array of technology to assist with defining property lines, from diopters to 3-D scanners. As new tools emerge, surveyors have been able to shape the profession, increasing precision, knowledge of land evolution, and interest in land professions.
B.C. Surveying Tools
Egyptians in 1400 B.C. were the first surveyors documenting their techniques. On the list of Egyptian surveying tools were sighting and leveling instruments, ropes, and plumb bobs. To collect taxes and keep a record of land ownership, ancient Egyptians ensured precision by constructing calculated methods of surveying. A solid truth still recognized today, recording appropriate land boundaries is critical to protecting land and wealth.
Nearly a thousand years later, magnets were used in China to determine direction, a predecessor to modern compasses. The diopter soon became the instrument of choice for surveyors after the development of geometry. Allowing professionals of the era the freedom of mobility, diopters accurately calculated the division of land while offering a convenient alternative to ropes, chains, and sighting instruments. Though not extremely complex, this instrument paved the way for surveyors to explore while practicing their craft.
Astronomers Contribute to Surveying
By implementing simple navigation tools, Arab surveyors in the 10th century perfected the art of celestial guidance and, eventually, affected the future of surveying as a profession. Starting with the use of a kamal, a specially designed measuring tool, Arab explorers refined the practice of surveying to include the use of modern instruments. The astrolabe and quadrant influenced the surveying discipline, as they provided new insights into the profession. Half a millennium later, the groma, an instrument used to create 45 or 90 degree alignments, was developed and widely used by surveyors.
Inventions of the 18th Century
Over the next 900 years, surveyors experimented with a device called the cross-staff, which works in the same manner as its predecessor, the kamal. As the production of quadrants became refined, sextants, pentants, and octants were developed to enhance accuracy and ease of use. Because the quadrant, sextant, and other models were easier to carry and operate, surveyors began to replace older methods with these inventions. Prior to the turn of the century, the theodolite was developed and systematically altered surveying, as it played an integral role in triangulation.
Surveying Blossoms in the 19th Century
For topographical surveying, 19th century inventors designed the alidade, which was for many years considered the most efficient method of surveying. The alidade simplifies the process of mapping topography and is used in conjunction with a plane table. The transit, designed by William Young, was introduced in the 1830s, resulting in increased accuracy and ease of land surveying. Placed on a tripod, the transit was welcome relief for land professionals of the time who had grown tired of outdated survey instruments. At the same time, Australians created Gunter’s chain and the steel measuring band to perfect surveying techniques.
Navigation Techniques Improve
To learn more about surveying instruments and their evolution to present day, stay tuned for part two where we’ll explore the many ways in which computers influenced the future of surveying.
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