Henri Pitot

Henri Pitot (1695 to 1771) was a French hydraulic engineer and the inventor of the Pitot tube. In 1732, while investigating the flow of the Seine, he established the relationship between fluid velocity and stagnation pressure. In a Pitot tube the fluid entering the inner tube is brought to rest, and the resulting stagnation pressure can be read on a pressure gauge or manometer or passed to an enclosed chamber such as the float bowl of a carburetor. When the manometer holds the same fluid as the flow being measured, the difference in height of the fluid columns for stagnation and static pressure is proportional to the square of the flow velocity. He rose to fame with the design of the Aqueduc de Saint-Clément near Montpellier, which took thirteen years to build, and with the extension of the Pont du Gard at Nîmes. He became a member of the French Academy of Sciences in 1724 and a fellow of the Royal Society in 1740. The Pitot theorem of plane geometry bears his name, and a street in Carcassonne is named after him.