Sir William Crookes was perhaps not the most self-effacing man in Victorian science, but he did have a sense of humour. His punning Latin motto, Ubi Crux Ibi Lux, was transformed by Vanity Fair cartoonist ‘Spy’ into Ubi Crookes Ibi Lux – ‘Where there is Crookes, there is light’. Overblown? Perhaps; but Crookes was a larger-than-life figure with a beard to match.
His motto referred equally to his investigations into electricity and his enthusiastic uptake of electric light – his house at 7 Kensington Park Gardens was the first in England to be lit in this way. But Crookes didn’t confine his research to one area, and he was not content with science for its own sake. He developed a new photographic process, founded and edited a popular chemistry journal, and discovered a new element, thallium. He famously (perhaps recklessly) delved into the world of psychic phenomena, becoming convinced that the psychic realm should be studied by scientists. At the same time, he worked to translate scientific research into money-making ventures, which included using sewage for fertilizer and a new method of gold extraction.
Crookes worked at the very beginning of the science that would become modern nuclear physics. His experiments with the ‘Crookes tube’, an evacuated glass vessel through which an electric current was passed, led to the discovery of X-rays and electrons (and paved the way for the invention of television). This came about while Crookes was trying to explain the workings of another device, the radiometer. Now occasionally sold as toys in science museum shops, the radiometer is a partially evacuated glass bulb enclosing a delicate wire apparatus on which hang thin vanes, black on one side and silver on the other. When exposed to a light source, the vanes spin around. Simple, you might think – light photons bounce off the shiny side of the vanes, pushing them around. But it’s not so simple. The vanes spin in the opposite direction from that predicted by this explanation.
Crookes and his friends were fascinated by these little devices and Crookes made sample after sample in all shapes and sizes to test out various theories. When he had finished his research he donated his radiometer collection to the Royal Society, including a tiny model set in a gold tie-pin. They have been kept in the Science Museum’s store for many years, but now a selection are on display as part of the Royal Society’s ‘350 Years of Science’ exhibition at Carlton House Terrace. A fascinating article about the radiometers by Jane Wess has just been published in Notes and Records of the Royal Society and is currently free to access; read to the end to learn what really makes radiometers spin!
In 1908 Crookes was nearing the end of his long career in science, but he was still an energetic experimentalist. Appointed to the Royal Society’s Glassworkers’ Cataracts Committee, he joined a group of Fellows investigating how men who spent their days looking at molten glass might be prevented from getting cataracts. In the recent film, Robert Downey Jr’s Sherlock Holmes completed his Victorian-chic outfit with a pair of sunglasses, but if Holmes did wear shades he was the only man in Victorian London to do so. It wasn’t until the 1920s that Crookes’s research led to large scale commercial production and eventually to polarised glass and modern sunglasses.