Leonardo da Vinci designed an anemometer to indicate changes in wind speed.
His version used a vertical plate that moved as wind acted on it. A graduated scale could show how far the plate was deflected, allowing an observer to compare wind strength. The instrument was mainly intended to study air movement in connection with flying machines.
An anemometer measures wind speed, while a wind vane indicates wind direction. Leonardo’s design was not the cup anemometer commonly seen at modern weather stations; it used a different principle based on wind pressure and displacement.
Leonardo’s notebooks repeatedly connect meteorology with flight. Understanding wind was essential to his studies of birds, gliding, and winged machines. His instrument was an early attempt to turn observations of moving air into a measurable quantity.