Windvanes—simple instruments to indicate wind direction—were known since antiquity. Vitruvius mentions them in De architectura. Ignazio Danti designed a windvane capable of actuating a small arrow placed on a vertical quadrant. In the 18th C, several types of windvane were built, whose movements were recorded with various methods. The most noteworthy models include the one designed by Christopher Wren—which formed part of a meteorographic complex—and the one installed in Milan by Marsilio Landriani. In the 19th C., these instruments proliferated, and around 1850 electricity was applied to apparatus for recording wind direction.
The first type of anemometer, an instrument to measure wind velocity, was described by Leon Battista Alberti in 1450 and again by Leonardo da Vinci. The instrument was fitted with a mobile tablet whose tilt gave a measure of wind force. Anemometers fitted with mobile vanes or propellors probably derived from windmills; the concept was applied, for example, by Robert Hooke after around 1670. A host of such devices were developed from the 18th C. onwards. Among the most significant was the recording anemometer invented by the Frenchman Ons-en-Bray in 1734—a jewel of applied mechanics. Another proposal was an anemometer in which the wind pressure caused a liquid column to rise up a tube. A model still in use today was developed in 1845 by the Irish astronomer Thomas Robinson. His device is fitted with a wheel carrying three or more arms that hold metal goblets set in motion by the wind. The goblets serve as a counter. Wind velocity is determined from the number of revolutions per time unit. The 19th C. saw a massive dissemination of devices to record wind direction and velocity, which were often part of large meteorographic complexes. In the 20th C., many of the previously developed devices were standardized to allow the collection of consistent data on wind force and velocity.
Maker unknown, first half 19th cent.
Maker unknown, 18th cent.
Maker unknown, Base: late 17th cent. / Horse: late 16th cent.
Maker unknown, late 18th cent.