Leonardo da Vinci improved the anemometer, an instrument used to indicate wind speed.
His design used a vertical plate that moved as wind pushed against it. The position of the plate could be read against a graduated scale, allowing an observer to estimate the strength of the wind. Leonardo’s version is commonly described as an early plate anemometer and is associated with his studies of flight and atmospheric movement.
Anemometers later developed into several forms. Cup anemometers use rotating cups, while propeller anemometers use a small rotor. Modern instruments may use ultrasonic pulses or laser measurements instead of moving parts.
Leonardo’s device did not provide the precision of modern meteorological equipment, and it was not the same as a barometer, which measures air pressure. Its historical importance lies in treating wind as something that could be measured systematically rather than merely described as calm or strong.