Elijah McCoy, born in Canada to runaway American slaves, showed so much promise in school that he won a scholarship to study mechanical engineering at Edinburgh University. McCoy moved to the US, where no one believed a black man could be an engineer and so he was set to stoking boilers. Nevertheless, McCoy devised a solution to one of the greatest problems facing steam locomotion that was sold worldwide with the marketers' proviso that McCoy's race be concealed.