These swan Barometers are pretty neat weather

forecasters. Just fill the swan's body with water and

 a few drops of food coloring if you would like. As

the air pressure rises and falls the water will move

 up and down the swan's neck. Depending on the

weather conditions when you fill up your swan, the

raising and lowering of  the water will tell you whether

 to expect clear skies, or a rainy day.