Is it a perpetual motion machine, or is it something more than that? The Second Law of Thermodynamics states that energy can neither be created nor destroyed in a closed system. So how does that relate to our little glass birdie here? The goop in his butt is methylene chloride, which has a very low boiling point, and therefore evaporates quickly. At room temperature, one or two degrees temperature difference causes the bright red chemical to climb to his head. Suddenly topheavy, he falls over. The felt head, soaked in the water from the cup, cools the methylene chloride, and it drains back to the bottom. The bird rights itself, and it starts all over again