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Albury Church,
Albury, England
51° 13′ 11.83″ N 0° 28′ 44.26″ W
William Oughtred
For almost 50 years (until his death in 1660), the British mathematician and clergyman William Oughtred was rector of Albury Church near Guildford, England. During that half-century, Oughtred volunteered his time to teaching mathematics to interested students. These students included mathematician John Wallis (who later became a cryptographer and was involved in the invention of calculus) and Sir Christopher Wren (celebrated architect, astronomer, and founder of the Royal Society).
Prior to becoming a clergyman, Oughtred was a fellow of King’s College, Cambridge, which he had attended since he was 15 years old. He became a fellow at the age of 21. Oughtred’s dedication to mathematical education led him to provide not only free tuition, but free lodging as well. Accounts of his life indicate that he liked to study late into the night, and was often still in bed the next day at noon. His church salary of £100 per year seems to have adequately provided for Oughtred and his wife, leaving him free to study, publish, and teach (when he was not busy tending to his congregation).
Oughtred published books designed to help students of mathematics, and that brought together his knowledge of the subject in a compact form. The books, written in Latin, also included many mathematical symbols of Oughtred’s own devising; today, the only symbol that remains in common use is the × for multiplication.
Oughtred’s most important contribution to mathematics, however, was the invention of the slide rule. Prior to Oughtred, various types of rule had been used (often in conjunction with a pair of calipers) to perform complex calculations. Galileo Galilei is usually credited with the invention of the sector during the 16th century, which was used for simple calculations (multiplication and division) as well as complex ones (trigonometry and square roots).
But the invention of the logarithm by John Napier in the early 1600s (see Chapter 57) laid the theoretical foundation that made the slide rule possible. The logarithm turned a problem of multiplication or division into one of addition or subtraction. Since addition and subtraction are easy to calculate, this made multiplication and division simple. By placing logarithmic scales on a pair of rods or a pair of concentric circles, accurate multiplication and division could be done without calipers by sliding the rods to align the numbers to be multiplied or divided, and then reading the result directly from the rule.
The slide rule was further refined in 1675 by Sir Isaac Newton, who added a movable cursor: a line used to mark a position on the slide rule. Others (including steam pioneer James Watt) improved the slide rule by adding scales that enabled fast calculation of square and cube roots, and in 1851 Amédée Mannhein, a French military officer, created a standardized slide rule with four scales (labeled A, B, C, and D). This would remain in use until the slide rule’s demise, which was brought about by the widespread availability of electronic computers and calculators in the 1960s.
For 300 years, the slide rule was the method of performing arithmetic for any engineering or scientific pursuit. Albert Einstein calculated using one, Wernher von Braun used them to do his rocketry calculations, and the Apollo astronauts took slide rules with them as a back-up calculating mechanism. Even the F-16 Fighting Falcon aircraft was designed using slide rules.
The parish of Albury has changed radically since Oughtred’s time. The original Saxon church where Oughtred preached was closed in 1840 and was replaced by three other churches in the parish: St Michael’s (a converted 19th-century barn), the Catholic Apostolic Church, and St. Peter and St. Paul (located in the heart of Albury).
However, the church building itself is preserved by the Churches Conservation Trust and is open to the public, as well as being occasionally used for services. Sitting in the peaceful Albury Park (which includes a large, privately owned home used for conferences and other functions), the church is nestled among trees and is a stone’s throw from the River Tilling. The church door dates back to the 13th century, and the interior has parts dating from the 15th through the 19th centuries. A small plaque in the church indicates that Oughtred is buried in the chancel, but there are no other markings of his grave.
Visit in January or February, and the church is surrounded by snowdrops. Any time you choose to visit, it’s a beautiful spot to contemplate the life and work of a self-taught mathematician, and to ponder the logarithm and the slide rule. It was an invention made by candlelight that, in the hands of engineers, helped to usher in the Steam Age, the Jet Age, and the Space Age.
Practical Information
For information about visiting the Albury Church, go to the Albury Parish website at http://www.alburychurches.org/. For more on William Oughtred and the slide rule, visit the Oughtred Society at http://www.oughtred.org/.
