1. Thermometer Toy This is a shaped twisted glass toy filled with liquid. Inside the bottle is a purple liquid. When heat is transferred from your bare hands, it will boil. 2. Boiling Principle: The operation of this toy is based on the speed at which the liquid boils and rises. Simply hold the larger bulb in your palm and gently grasp it with your hand. Wait a few minutes for your body heat to transfer to the glass, causing the liquid to rise. Be careful—it is made of glass and very fragile. 3. Scientific Demonstration: The heat from your hands brings the liquid to a boil, causing it to evaporate into gas. The expanding gas pushes the liquid upward. When you release your hand, equilibrium is restored as the gas condenses back into liquid and flows down into the lower container. This is a fascinating scientific toy and a example of energy transfer. 4. Learning Tool The liquid boils at body temperature. Hold the lower container in your hand—the glass surface makes it easy to observe how the liquid boils and rises through the tube into the upper container, demonstrating gasliquid equilibrium. The colored liquid inside is a volatile mixture with a boiling point just above room temperature, making it an physics demonstration for children. Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.