饮水鸟

饮水鸟也叫喝水鸟、永动鸟，是一种根据热机原理制作的一种由美国人万里诉沙利文（Miles V. Sullivan）在西元1942年所设计的玩具。一般由玻璃制成。当“鸟头”被润湿时，由于水蒸发带走了热量，使头部的气压降低，鸟身体内的液体被吸到头部，使得身体头重脚轻，鸟头因过重而往前倾，当身体接近水平时体内两端空气又开始流通，压强平衡，头部的液体又回到体内，鸟头恢复初始状态。如果前面放有水，使鸟头前倾时能够沾到，保持鸟头湿润，则此过程即可反复进行。

参考资料
 国立清华大学

外部链接

 Video comparing two common drinking birds in action.
 How a drinking bird works. 
 Drinking bird movies and images 
 gallery of variations, and "care guide"
 modification guide for a purely solar-powered bird 
 art project by Daniel Reynolds 
 Miles V. Sullivan designed the Drinking Bird in 1945 - filed for patent 2,402,463 on Aug 6, 1945
 Drinking Duck:  Demonstration experiment (instruction and video)
  Who invented the drinking bird?
 The effects of ethanol on Drinking bird 

益智玩具
热力学
新奇物品