Felix Andries Vening Meinesz (30 July 1887 – 10 August 1966) was a Dutch geophysicist and geodesist. He is known for his invention of a precise method for measuring gravity (gravimetry). Thanks to his invention, it became possible to measure gravity at sea, which led him to the discovery of gravity anomalies above the ocean floor. He later attributed these anomalies to continental drift. He was a Fellow of the Royal Society. Biography Vening Meinesz's father, Sjoerd Anne Vening Meinesz, was mayor, first of Rotterdam, then of Amsterdam. Felix was born in The Hague grew up in a protected environment. In 1910 he graduated in civil engineering in Delft. The same year he started working for the Dutch gravity survey. In 1915 he wrote his dissertation on the defects of the gravimeters used at that time. Vening Meinesz then designed a new gravimeter, which the KNMI (Royal Dutch Meteorological Institute) built. The apparatus has two pendula of the same size hanging in a frame but moving in opposite phases. With mirrors and lightbeams the difference in amplitude of the two pendula is captured on a film. Vening Meinesz had discovered that horizontal accelerations (as by waves on a boat) had no influence on the difference in amplitude between the two pendula. The recorded difference then is the amplitude of a theoretical, undisturbed pendulum. Now it became possible to measure gravity more accurately. Vening Meinesz started with measuring gravity all over the Netherlands, for which a network of 51 monitoring stations was created. This became a success, which encouraged him to do measurements at sea. A perfected gravimeter, hanging in a 'swing', was designed. The experiment was successful. Now measuring gravity at sea had become possible. Between 1923 and 1929 the tall (over 2 metres) Vening Meinesz embarked in small submarines for some uncomfortable expeditions. His goal was to establish the exact shape of the geoid and the Earth. When his expedition with the submarine Hr. Ms. K XVIII was made into a movie in 1935, Vening Meinesz became a hero of the Dutch cinema public. Besides, his research was in the international scientific spotlight. In 1927 he became a part-time professor in geodesy, cartography and geophysics at Utrecht University, and in 1937 he became professor at the Delft University of Technology as well. In 1927 he became member of the Royal Netherlands Academy of Arts and Sciences. He was awarded