A device for measuring the speed of a fluid. It consists of two tubes, one with an opening facing the moving fluid and the other with an opening at 90° to the direction of the flow. The two tubes are connected to the opposite sides of a manometer so that the difference between the dynamic pressure in the first tube and the static pressure in the second tube can be measured. The speed v of the flow of an incompressible fluid is then given by: v2=2(P2 − P1)/ρ, where P2 is the dynamic pressure, P1 is the static pressure, and ρ is the density of the fluid. The device has a wide variety of applications. It was devised by the Italian-born French engineer Henri Pitot (1695–1771).