http://www.overunity.com/index.php/topic,2421.0.html
Hello FreeEnergy,
it is not necessary to heat the water to keep a Drinking Bird moving. The principle is based on evaporation and capillary effect.
The head is usually coated in a red felt-like material which absorbs water when the bird "drinks". Evaporation of water from the head causes the head to become cooler than the body. Although the head and upper part of the glass tube appear to be "empty", they are actually full of invisible vapour from the methylene chloride. Methylene chloride is good for this because it doesn't take much heat energy to turn it into a vapour (It has a "low latent heat of evaporation"). Because the head is cooler than the body, some of this vapour condenses inside the head, causing the liquid to be sucked up the tube. This makes it tip over more and more until eventually it tilts into the water. The liquid which has moved up towards the head now gurgles back down into the body. This rapidly moves the centre of gravity back to the lower body, and the bird swings back away from the glass. Now the process starts again until there is no more water to keep the bird oscillating.
Regards
Andreas Varesi
http://www.overunity.com/index.php/topic,2421.0.html
gets me thinking, I've done some research on refidgerants and I think that
methylene chloride deserves some attention maybe