Leonardo da Vinci designed an anemometer, an instrument for measuring wind speed.
His design used a light, movable plate that wind pushed upward. The height reached by the plate could be read against a graduated scale, providing an indication of wind strength. It was a mechanical way to turn invisible airflow into a visible measurement.
Leonardo studied wind for both scientific observation and practical engineering. Understanding airflow mattered to his investigations of flight, weather, sails, and the movement of objects through the air.
An anemometer measures wind speed, while a wind vane indicates wind direction. Leonardo’s instrument should also be distinguished from a hygrometer, which measures humidity, and a barometer, which measures atmospheric pressure.