LAUSR

Silvanus Phillips Thompson (1851–1916, Figure 1) is celebrated for the wide-ranging researches he conducted, particularly in engineering. He commanded enormous scientific respect for his work on magnetism, electricity, light and x-rays. In 1896, he delivered the Christmas Lectures at the Royal Institution on Light visible and invisible (Thompson, 1897) and again in 1910 on Sound musical and non-musical (although he made no printed account of these). His forays into visual and auditory perception were penetrating, but they have not received the recognition they deserve. He investigated a range of visual motion illusions and carried out some of the first experiments on binaural hearing. Thompson was born in York and received his early education at Bootham School, a Quaker institution at which he later became a teacher. He studied at the School of Mines in London and moved to Bristol University in 1876, becoming Professor of Physics in 1878. From 1885 until he died, he was Principal and Professor of Applied Physics at Finsbury College, London. His biography, written by his wife and daughter, commenced ‘Measured in years, the life of Silvanus Phillips Thompson was not a long one; but each day and each year was full, and in that sense long’ (Thompson & Thompson, 1920, p. v). Throughout his life, Thompson remained fascinated by light and its effects although it was largely in the late 1870s, during his tenure at Bristol University, that he engaged in perception research and published papers on vision and hearing. Thompson was a lucid lecturer and his initial account of the motion aftereffect (MAE) was delivered to a meeting of the 1877 British Association for the Advancement of Science (BAAS), held at Plymouth. Thompson extended observations of MAEs seen from a moving train to depth as well as direction: