Globe Storm Glass Barometer works by changes in the air pressure which cause the level of liquid in the barometer to move up and down, allowing you to predict changes in the weather. If the liquid in the spout is lower than the liquid in the globe then fair weather is on the way! If the liquid in the spout is higher than the liquid in the globe then a storm may be approaching especially if the water nears the top of the spout! After observing the changes in the balance of water between the globe and the spout in relation to the weather patterns you will learn how to use it to predict fair or stormy weather. Includes clear globe style storm glass barometer, syringe, tube for easy filling and step by step filling instructions. Add a little of your own food color to the water and make it the color of your choice.