The pyramid inch is a now discredited unit of measure formerly claimed by pyramidologists to have been used in ancient times.

History

The first suggestion that the builders of the

Great Pyramid of Giza The Great Pyramid of Giza is the largest Egyptian pyramid. It served as the tomb of pharaoh Khufu, who ruled during the Fourth Dynasty of Egypt, Fourth Dynasty of the Old Kingdom of Egypt, Old Kingdom. Built , over a period of about 26 years ...

used units of measure related to modern measures is attributed to

Oxford Oxford () is a City status in the United Kingdom, cathedral city and non-metropolitan district in Oxfordshire, England, of which it is the county town. The city is home to the University of Oxford, the List of oldest universities in continuou ...

astronomy professor

John Greaves John Greaves (1602 – 8 October 1652) was an English mathematician, astronomer and antiquarian. Education Educated at Balliol College, Oxford, he was elected a Fellow of Merton College in 1624. He studied Persian and Arabic, acquired a ...

(1602–1652), who journeyed to Egypt in 1638 to make measurements of the pyramid. His findings were published in his ''Pyramidographia'' (1646) and under his name in an anonymous tract. More than a century later, Greaves' measurements and additional measurements made by French engineers during

Napoleon Napoleon Bonaparte (born Napoleone di Buonaparte; 15 August 1769 – 5 May 1821), later known by his regnal name Napoleon I, was a French general and statesman who rose to prominence during the French Revolution and led Military career ...

's campaign in Egypt and Syria, were studied by John Taylor (1781–1864). Taylor claimed that the measurements indicated that the ancients had used a unit of measure about 1/1000 greater than a modern British inch. This was the origin of the "pyramid inch". Taylor regarded the "pyramid inch" to be 1/25 of the "sacred

cubit The cubit is an ancient unit of length based on the distance from the elbow to the tip of the middle finger. It was primarily associated with the Sumerians, Egyptians, and Israelites. The term ''cubit'' is found in the Bible regarding Noah ...

", ancient unit based on the forearm length from the tip of the middle finger to the bottom of the elbow, whose existence had earlier been postulated by

Isaac Newton Sir Isaac Newton () was an English polymath active as a mathematician, physicist, astronomer, alchemist, theologian, and author. Newton was a key figure in the Scientific Revolution and the Age of Enlightenment, Enlightenment that followed ...

. The principal argument was that the total length of the four sides of the pyramid would be 36524 (100 times the number of days in a year) if measured in pyramid inches. Taylor and his followers, who included the Astronomer Royal of Scotland

Charles Piazzi Smyth Charles Piazzi Smyth (3 January 1819 – 21 February 1900) was a British astronomer who was Astronomer Royal for Scotland from 1846 to 1888; he is known for many innovations in astronomy and, along with his wife Jessica Duncan Piazzi Smyth, hi ...

(1819–1900), also found numerous apparent coincidences between the measurements of the pyramids and the geometry of the Earth and the

Solar System The Solar SystemCapitalization of the name varies. The International Astronomical Union, the authoritative body regarding astronomical nomenclature, specifies capitalizing the names of all individual astronomical objects but uses mixed "Sola ...

. They concluded that the British system of measures was derived from a far more ancient, if not divine, system. During the 19th and early 20th centuries, this theory played a significant role in the debates over whether Britain and the United States should adopt the

metric system The metric system is a system of measurement that standardization, standardizes a set of base units and a nomenclature for describing relatively large and small quantities via decimal-based multiplicative unit prefixes. Though the rules gover ...

. The theory of Taylor and Smyth gained many eminent supporters and detractors during the following decades, but by the end of the 19th century it had lost most of its mainstream scientific support. The greatest blow to the theory was dealt by the Egyptologist

Flinders Petrie Sir William Matthew Flinders Petrie ( – ), commonly known as simply Sir Flinders Petrie, was an English people, English Egyptology, Egyptologist and a pioneer of systematic methodology in archaeology and the preservation of artefacts. ...

(1853–1942), whose father was a believer. When Petrie went to Egypt in 1880 to perform new measurements, he found that the pyramid was several feet smaller than previously believed, including the missing capstone. This so undermined the theory that Petrie rejected it, writing "there is no authentic example, that will bear examination, of the use or existence of any such measure as a ‘Pyramid inch,’ or of a cubit of 25.025 British inches."W. M. Flinders Petrie, ''The Pyramids and Temples of Giza'' (London, 1883), p18

The pyramid inch now appears to have no significant scientific support. No direct evidence for it has ever been found.

References

{{reflist, 2 Obsolete units of measurement Pyramidology Numerology Great Pyramid of Giza