Silvanus Phillips Thompson was an electrical engineer, professor of physics, and a gifted communicator of scientific ideas. Like other Quaker scientists before and since, he drew parallels between the quests for truth in his science and in his faith.
The son of one of the schoolmasters at Bootham School in York, England, he studied there himself and for a time taught science, before going on to study physics and chemistry at the Royal School of Mines in London. Stimulated by a lecture he heard at the Royal Institution, he developed a particular interest in light and optics. In 1876, he was appointed lecturer in physics at University College, Bristol, becoming Professor of Physics in 1878, at the age of just 27. In 1885, his interest in Higher Education led him to become Director of Finsbury Technical College in London, an offshoot of City and Guilds College, where he stayed for thirty years.
In 1891, Thompson registered a patent for a submarine cable for telegraph communication: using two wires as separate conductors connected by an induction coil, similar in concept to modern coaxial cables. This allowed for a significant increase in the speed words could be transmitted along the cable.
Thompson repeated Röntgen's experiments with X-rays the day after they were announced in the UK, and gave what was evidently a remarkable first public demonstration of them at the Clinical Society of London in March 1896. That same year, he delivered the Royal Institution Christmas Lectures, on Light, Visible and Invisible.
Thompson was elected Fellow of the Royal Society in 1891. He was the first President of the Röntgen Society (now The British Institute of Radiology) and in 1899 became President of the Institute of Electrical Engineers. He wrote a large number of books, including biographies of the scientists Kelvin and Faraday, and several that were regarded as seminal texts in electromagnetism. However, his best known work, still in print today, was Calculus Made Easy, first published in 1910.
In 1915, Thompson gave his Swarthmore Lecture, The Quest for Truth, in which he again drew parallels between his approaches to religion and to science. He described the Inner Light as working in scientists through their intuitions. He warned against ready-made religious systems and suggested that, as in science, new understanding came in small increments, resulting from many minds working together.
He died in 1916, deeply troubled by the unfolding war in Europe.
Since 1918, the British Institute of Radiology have held an annual Silvanus Thompson memorial lecture for which they award a silver medal.