1574 – Born on March 5th in Eton, Buckinghamshire, England. English mathematician and Anglican minister who invented the earliest form of the slide rule, two identical linear or circular logarithmic scales held together and adjusted by hand. Improvements involving the familiar inner sliding rule came later.
1596-1600 – Oughtred was educated at Eton College and at King’s College, Cambridge, where he received his bachelor’s degree and master’s degree.
1603 – His ordainment as an Anglican priest.
1604 – Appointed as vicar of Shalford.
1610 – He became rector of Albury, where he remained until his death.
1630 – A former student of his and tutor to King Charles I of Great Britain, Richard Delamain, published a small pamphlet in which he claimed to have invented that instrument, and an acrimonious controversy ensued.
1631 – He consented to allow the printing of a small manual that he had utilized in teaching one of his students. The book became famous under the title of Clavis Mathematicae (“The Key to Mathematics”), although it was not an easy text.
1632 – Oughtred described his circular slide rule in Circles of Proportion and the Horizontal Instrument, which, in addition to defending his reputation and priority during the controversy, addressed the important issue of the proper role of theory and instruments in the teaching of mathematics—a subject of continuing debate.
1660 – Died on June 30th in Albury, Surrey.
1677 – Oughtred’s other writings were published by his students much later, including Trigonometria (“Trigonometry”) and a posthumous collection of tracts, Opuscula mathematica hactenus inedita (“Unpublished Mathematical Papers”).