Oliver Heaviside (May 18, 1850 - February 3, 1925) was a self-taught English electrical engineer, mathematician, and physicist who adapted complex numbers to the study of electrical circuits, invented mathematical techniques to the solution of differential equations, reformulated Maxwell's field equations in terms of electric and magnetic forces and energy flux, and independently co-formulated vector analysis. Although at odds with the scientific establishment for most of his life, Heaviside changed the face of mathematics and science for years to come. In later years his behavior became quite eccentric. Though he had been an active cyclist in his youth, his health seriously declined in his sixth decade. During this time he would sign letters with the initials, W.O.R.M., after his name. He also reportedly started painting his fingernails pink and had granite blocks moved into his house for furniture. He died in 1925 at the age of 75. Most of his recognition was gained posthumously.