Leonardo da Vinci’s anemometer was designed to record wind speed.
An anemometer is an instrument used to measure how fast air moves. Leonardo’s design used a hinged plate: stronger wind pushed the plate farther upward, and a graduated scale indicated the wind’s force. This made the device an early attempt to turn an invisible weather condition into a measurable reading.
Leonardo studied wind because it affected flight, sailing, clouds, and atmospheric motion. His anemometer was not the cup-style instrument commonly seen on modern weather stations, which was developed much later. It was also not intended to measure wind direction; that requires a separate instrument, such as a weather vane.
The design belongs to Leonardo’s broader investigations of air and flight. Although his notebooks contained many ingenious ideas, not every drawing became a practical working device. His anemometer is remembered as an important early concept in meteorological instrumentation.