On this day in 1874, inventor Lewis Latimer received his first patent. The son of a Virginia couple who had escaped from slavery, he was born and raised in Chelsea. After a stint in the Union Army, Latimer began his career as an office boy in a Boston patent firm. Over 50 years later, he ended it as one of the "Edison Pioneers," a group of distinguished men who had helped establish the electric light industry. In between, Lewis Latimer was instrumental in helping Thomas Alva Edison develop the incandescent light bulb. He was awarded patents for ten of his own inventions and published a layman's guide to the once mysterious, now ubiquitous, electric light bulb.