Peter Guthrie Tait, Scottish mathematician and physicist, 1884.
© Science Museum / Science & Society Picture Library
Etching by W Hole from 'Quasi Cursores'. Peter Guthrie Tait (1831-1901) conducted experiments to determine the density of ozone and the effects of pasing electrical discharge through oxygen and other gases. He also carried out research using quaternions (complex numbers) in relation to electrodynamics and magnetism. He was Chair of Mathematics at Queen's College Belfast from 1854, and was appointed Profesor of Natural Philosophy at Edinburgh University in 1860. He wrote a number of physics textbooks, most notably 'A Treatise on Natural Philosophy' (1867-1883).