"In 1916 and 1917 de Sitter presented to the Royal Astronomical Society a series of three papers on "Einstein's Theory of Gravitation and its Astronomical Consequences." Because there was no communication between Germany and England during World War I, these papers were instrumental in introducing general relativity to the English scientific community, and they played an important part in the decision of Arthur Eddington and others to send expeditions to observe the solar eclipse of 1919..."