The Origin and Reading of the Weather Vane

Long before satellites and radar, people tracked the wind with a simple spinning tool: the weather vane. The oldest known example sits on top of the Tower of the Winds. This is an eight-sided marble structure built in Athens around 48 BCE by the astronomer Andronicus of Cyrrhus. A bronze figure of Triton, the Greek sea god, once turned in the wind on top of the tower. His outstretched hand showed the direction the wind was blowing from. This design spread through the Roman world. Centuries later, it took a very different form in medieval Europe: the rooster. According to church tradition, Pope Nicholas I ordered in the ninth century that every church should display a rooster on its steeple. This was a reminder of a biblical story, in which a rooster's crow marked the apostle Peter's denial of Christ. Reading a weather vane, whether shaped like a sea god or a rooster, follows one simple rule. This rule often confuses people at first. The pointed front of the vane swings to face into the wind. So it shows where the wind is coming from, not where it is going. If a vane points toward a fixed "N" marker, this means the wind is blowing out of the north.