Henri Pitot was a French hydraulic engineer and the inventor of the pitot tube. In a pitot tube, the height of the fluid column is proportional to the square of the velocity of the fluid at the depth of the inlet to the pitot tube.
Beginning his career as a mathematician and astronomer, Pitot won election to the Academy of Sciences in 1724. He became interested in the problem of flow of water in rivers and canals and discovered that much contemporary theory was erroneous. He devised a tube, with an opening facing the flow, that provided a convenient and reasonably accurate measurement of flow velocity and that has found wide application .

In a pitot tube, the height of the fluid column is proportional to the square of the velocity. This relationship was discovered intuitively by Henri Pitot in 1732, when he was assigned the task of measuring the flow in the river Seine.
He rose to fame with the design of Aqueduc de Saint-Clément near Montpellier and the extension of Pont du Gard in Nîmes. In 1724, he became a member of the French Academy of Sciences, and in 1740 a fellow of the Royal Society.
The Pitot theorem of plane geometry is named after him.Appointed chief engineer for Languedoc, he performed a variety of maintenance and construction work on canals, bridges, and drainage projects. His major work was construction of an aqueduct for the city of Montpellier (1753–86), including a stone-arch Roman-type section one kilometre (more than one-half mile) in length.
With subsequent improvements by Henri Darcy, its modern form is used to determine the airspeed of aircraft.