October 20: Christopher Wren

Sir Christopher Wren

October 20, 1632 – February 25, 1723

Christopher Wren was one of the best known and highest acclaimed English architects in history, responsible for rebuilding 55 churches in the City of London after the Great Fire in 1666, including his masterpiece St Paul's Cathedral, completed in 1710.

Educated in Latin and Aristotelian physics at the University of Oxford, Wren was a notable astronomer, geometer, mathematician-physicist as well as an architect. He was a founder of the Royal Society (president 1680–82), and his scientific work was highly regarded by Sir Isaac Newton and Blaise Pascal.

One of Wren's friends, another great scientist and architect in his time, Robert Hooke said of him "Since the time of Archimedes there scarce ever met in one man in so great perfection such a mechanical hand and so philosophical mind."

When a fellow of All Souls, Wren constructed a transparent beehive for scientific observation; he began observing the moon, which was to lead to the invention of micrometers for the telescope. He experimented on terrestrial magnetism and had taken part in medical experiments, performing the first successful injection of a substance into the bloodstream (of a dog).

In Gresham College, he did experiments involving determining longitude through magnetic variation and through lunar observation to help with navigation, and helped construct a 35-foot (11 m) telescope with Sir Paul Neile. Wren also studied and improved the microscope and telescope at this time. He had also been making observations of the planet Saturn from around 1652 with the aim of explaining its appearance. His hypothesis was written up in De corpore saturni but before the work was published, Huygens presented his theory of the rings of Saturn. Immediately Wren recognized this as a better hypothesis than his own and De corpore saturni was never published. In addition, he constructed an exquisitely detailed lunar model and presented it to the king.

A year into Wren's appointment as a Savilian Professor in Oxford, the Royal Society was created and Wren became an active member. As a Savilian Professor, Wren studied thoroughly in mechanics, especially in elastic collisions and pendulum motions, which he studied extensively. He also directed his far-ranging intelligence to the study of meteorology, and fabricated a "weather-clock" that recorded temperature, humidity, rainfall and barometric pressure, which could be used to predict the weather.

Another topic to which Wren contributed was optics. He published a description of an engine to create perspective drawings and he discussed the grinding of conical lenses and mirrors. Out of this work came another of Wren's important mathematical results, namely that the hyperboloid of revolution is a ruled surface. These results were published in 1669. In subsequent years, Wren continued with his work with the Royal Society, although after the 1680s his scientific interests seem to have waned: no doubt his architectural and official duties absorbed all his time.

Mentioned above are only a few of Wren’s scientific works. He also studied in other areas not mentioned, ranging from agriculture, ballistics, water and freezing, to investigating light and refraction only to name a few. Thomas Birch's History of the Royal Society is one of the most important sources of our knowledge not only of the origins of the Society, but also the day to day running of the Society. It is in these records that the majority of Wren’s scientific works are recorded.