Leonardo da Vinci designed an anemometer to measure wind speed using the movement of a hinged plate.
Leonardo’s version used a vertical board or plate that could swing in the wind. A graduated scale allowed an observer to estimate the force or speed of the airflow from the plate’s angle. The design is commonly associated with Leonardo’s studies of flight and the behavior of air, where measuring wind conditions would have been valuable.
An anemometer is an instrument for measuring wind speed, although modern instruments may also record wind direction. Leonardo’s device was not the cup anemometer familiar from many weather stations. Cup anemometers use rotating cups, while his concept relied on wind pressure acting on a plate.
Leonardo’s notebooks contain many observations about air, birds, wings, and atmospheric motion. His anemometer belongs to that scientific program: before designing a flying machine, he sought ways to understand the medium through which it would move. The surviving drawing represents an early instrument concept, not evidence that Leonardo created a standardized meteorological network.