Weather-vane

A weather vane, wind vane, or weathercock is an instrument for showing the direction of the wind. They are typically used as an architectural ornament to the highest point of a building.

Although partly functional, weather vanes are generally decorative, often featuring the traditional cockerel design with letters indicating the points of the compass. Other common motifs include ships, arrows and horses. Not all weather vanes have pointers.

The word 'vane' comes from the Old English word fana meaning 'flag'.

The Tower of the Winds on the ancient Greek agora in Athens once bore on its roof a wind vane in the form of a bronze Triton holding a rod in his outstretched hand, rotating as the wind changed direction. Below this was a frieze adorned with the eight Greek wind deities. The eight-metre-high structure also featured sundials, and a water clock inside. It dates from around 50 BCE.

The oldest existing weather vane with the shape of a rooster is the Gallo di Ramperto, made in 820 CE and now preserved in the Museo di Santa Giulia in Brescia, Lombardy.

Pope Leo IV had a cock placed on the Old St. Peter's Basilica or old Constantinian basilica.

Pope Gregory I said that the cock (rooster) "was the most suitable emblem of Christianity", being "the emblem of St Peter", a reference to in which Jesus predcits that Peter will deny him three times before the rooster crows.

As a result of this, the cock gradually began to be used as a weather vane on church steeples, and in the 9th century Pope Nicholas I ordered the figure to be placed on every church steeple.

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