Stokes, Sir George (Gabriel)
Physicist and mathematician, born in Skreen, Co Sligo, W Ireland. He studied at Cambridge, where in 1849 he became professor of mathematics. He first used spectroscopy as a means of determining the chemical compositions of the Sun and stars, published a valuable paper on diffraction (1849), and formulated Stokes' law for the force opposing a small sphere in its passage through a viscous fluid. He was secretary of the Royal Society for 30 years (from 1854), then became its president. He was created a baronet in 1889.