He was a Fellow of the Royal Society. In 1888 he began work at the Cavendish Laboratory under J.J. Thomson, and ended up working with the lab for fifty-five years. His influence extended well into the nineteenfifties, for he was brought back to run the undergraduate labs during and after World War II. I well recall his pinning a note on the back of a student saying "mediocre". His equipment, used to calibrate the Ohm, with Thompson about 1900, was still being used in the undergraduate lab of the Cavendish then. When he was a child, he had known Clerk Maxwell, and told me he was a very humorous individual, unlike his pictures. He wrote a book on Oliver Heaviside with whom he was very friendly. The book was completed in 1950. However, it remained unpublished for many years. It was finally published in 1987 by C.A.M. Publishing. He was married with Alice Mary Edwards. Searle might be characterized as a typical British eccentric. He had contracted a disease at the beginning of WW 1, was cured, and became a Christian Scientist, Being a keen cyclist, he travelled about proselytizing.
He is known for his work on the velocity dependence of the electromagnetic mass. This was a direct predecessor of Einstein's theory of special relativity, when several people were investigating the change of mass with velocity . Following the work of Oliver Heaviside, he defined the expression Heaviside ellipsoid, which means that the electrostatic field is contracted in the line of motion. Those developments, when modified, were ultimately important for the development of special relativity.
Searle was the author of numerous papers and a number of books: