Facts About Weathervanes And How They Work

A weather vane is located on a high structure. It cannot be obstructed by trees or buildings because their purpose is to catch the wind. It can determine from which direction a wind is blowing. In days gone by, weathervanes were very important, especially for farmers, for whom wind and weather were daily considerations.

The first weather vane was built in Ancient Greece by Andronicus, A Greek astronomer. It was built out of bronze in honor of Triton, a Greek god. A wand in his hand indicated wind direction from the top of a tower in Athens. Its head and torso were that of a man and it had the tail of a fish.

With the conversion of the Roman Empire to Christianity, a rooster began to appear on church steeples. It reminded believers of the need to be watchful because Jesus prophesied that Peter would deny him before the cock crowed three times. The tail of a rooster is just the right shape to catch the wind and its force is greater on the tail than the head. It gets pushed away so the head turns into the wind. This is probably why the rooster design remains so popular to this day. It also has symbolic relevance in that it welcomes the dawn and the triumph of light over darkness.

The pointer on the weather vane has to be the right shape and it has to move freely. The pointer is larger at one end and tapered at the other. The large end catches wind and turns to point where it is going while the small end swings to point to where it is coming from.

A weather vane that is shaped correctly and has balance will spin freely. If it is not precisely balanced, it will shift or topple and even stop moving. The weight needs to be equally distributed on either side of the axis or the vane will not spin freely. Some modern weather vanes do not have the necessary weight balance. They are designed more as architectural ornaments than for determining wind direction.

Beneath the point on a wind vane, it usually has fixed markers. There are four markers for each direction of the compass. If the arrow points toward the marker for south on the vane, it shows that wind is blowing from the south. If it is pointing to the west, wind is blowing from the west and towards the east.

When observers look at changing directions and wind patterns, they can make simple forecasts. Forecasts are based on other factors too, such as knowledge or experience of local climatic conditions. If they know that the north is cold and the south is warm, for example, they know what to expect when wind comes from that direction.

Knowing about where the wind was coming from was a great help to farmers in the past. They would examine the signs daily and put together their knowledge about the local area and climate to make their predictions. This could help them plant their crops in the right places and protect them. Today, we no longer need to determine weather by using weather vanes. We have plenty of modern instruments that are far superior. However, the appeal of this instrument remains and many people still enjoy placing them on their homes.