Nobel prize-winning scientist Sir George Porter explores the science behind man-made light and heat in this 1976 CHRISTMAS LECTURE. He recounts the history of artificial light sources such as lamps and the formation of natural fuel sources such as coal and oil. The Humphry Davy Lamp's role in saving the mining industry from explosions is explained. While the work of Count Rumford founder of the Ri’s work on convection and James Dewar’s Flask are also illustrated.