Happy Birthday, Christopher Wren!

Today is the birthday of Sir Christopher Wren, the English anatomist, astronomer, mathematician, and architect who helped rebuild Britain after the Great Fire of London, a conflagration which destroyed 436 acres, 87 churches and 13,200 houses in September of 1666. Wren was born on October 20, 1632 in East Knoyle, Wiltshire. His father, a rector in the Church of England, became the Dean of Windsor when young Christopher was just two years old. As a boy, Wren attended the Westminster School and sometimes played with the son of Charles I, the Prince of Wales. When the English Civil War interrupted Wren's education, the boy was forced to join his father at a rectory in Bletchingham, Oxfordshire. Soon, father and son were joined by Wren's sister and her husband, William Holder. According to Wren's biographers, Holder tutored Wren in mathematics and fostered his interest in astronomy.

Christopher Wren eventually returned to Westminster, but left the school in 1646. He experimented with sundials, created a model of the solar system, and served as an assistant to Dr. Charles Scarburgh, a teaching physician. Wren's first serious scientific contributions were the models of muscles that he created for Scarburgh's anatomy lectures. Wren also translated the work of William Oughtred, a mathematician who invented a primitive slide rule, into Latin. Eventually, Wren entered Wadham College, earning a B.A. in 1651 and an M.A. in 1653. While at Wadham, Wren sketched the human brain and devised a blood transfusion method, which he demonstrated on dogs. He also created an instrument for measuring angles, sketched water-lifting machines, and considered ways to find longitude and distance at sea.

Wren distinguished himself as a mathematician while serving as a professor of astronomy first at Gresham College and then at Oxford University. Using an exhaustion proof, he determined the length of an arc of a cycloid, the curve defined by a fixed point on a wheel as it rolls. Wren also confirmed Johannes Kepler's third law of planetary motion, which states the squares of the orbital periods of planets are directly proportional to the cubes of the semi-major axis of the orbits. Additional accomplishments include considerations of conical lenses and proof of the connection between elliptical orbits and the inverse-square law, an equation which relates the relative distances of two objects as compared to a third. While at Gresham College, Wren met informally with other leading intellectuals of the day. The Royal Society, the group that he helped found, eventually became England's national academy of science.

Wren's career as an architect began in 1663 when his uncle, the Bishop of Ely, asked him to design the chapel at Pembroke College, Cambridge. A year later, the erstwhile astronomer planned the Sheldonian Theatre at Oxford, the first of Wren's projects to include a dome. Subsequent work included the Emmanuel College Chapel, Cambridge and the Garden Quadrangle, Trinity College, Oxford. Wren's greatest opportunity in architecture came in 1666, when he was appointed Commissioner for Rebuilding the City of London. With the help of Robert Hooke, another eclectic scientist, Wren re-planned the entire city and supervised the rebuilding of 51 churches. Although the London City Council rejected two of Wren's plans for rebuilding the massive St. Paul's Cathedral, a third design was finally accepted in 1675. Fittingly, work on St. Paul's was completed on October 20, 1708, Wren's seventy-sixth birthday.

During the twilight of his life, Wren designed the Royal Observatory for Charles II, who had restored the monarchy in 1660 and now sought to help England surpass its sea-faring rivals. Wren also served as the Surveyor of Greenwich Naval Hospital and Surveyor of Westminster Abbey. He resigned the former role in 1716, but held the later until his death on February 25, 1723. Wren's body is buried in St. Paul's Cathedral, but his scientific and architectural contributions live on.