Sir William Lawrence Bragg giving one of the 1961 Christmas Lectures for Children at the Royal Institution, London. Bragg's lectures were on the nature of electricity, and he is shown next to two red spheres that are being charged with static electricity by his assistant. The Christmas Lectures were instigated by Faraday in 1825, and have been held annually ever since. Since 1965 the lectures have been televised. William Lawrence Bragg (1890-1971) was a British physicist. With his father William Henry Bragg, he discovered the diffraction of X-rays by crystals. This led to the technique of X-ray crystallography, a major analytical tool, and the Braggs sharing the Nobel prize for Physics in 1915. Bragg worked at the Royal Institution from 1953 and was a popular and gifted lecturer.