Fat Brain Toy The Thermodynamic Drinking Bird Discount

The science behind the very thirsty bird:
Water evaporates from the felt on the bird’s head.
Evaporation lowers temperature of the glass head.
The temperature decrease causes dichloromethane vapor in the head to condense.
The lower temperature and condensation cause pressure to drop in the head.
The higher vapor pressure in the warmer base pushes liquid up the bird’s neck.
The liquid rises and the bird becomes top heavy and tips over.
When the bird tips over, the bottom end of neck tube rises above the liquid’s surface.
A bubble of warm vapor moves up the tube through the gap, displacing liquid.
Liquid flows back to bottom bulb, pressure equalizes between top and bottom bulbs.
The weight of the liquid in bottom bulb restores the bird buddy to a vertical position.
The liquid in the bottom bulb is heated by ambient air, a temperature slightly higher than the temperature of the bird’s head.