This invention has made the rounds on YouTube and elsenet. In a nutshell, pop bottles embedded in a hut wall draw air in, and supposedly cool the air inside. As far as I can tell, they are claiming it is not just a cooling effect (due to increasing skin evaporation) but a temperature drop, measurable on a thermometer, by as much 5C. Certainly, there good reason to be skeptical. Can anyone shed some light as to whether there are established principles involved (venturi effect? adiabatic cooling?) - that make this at least plausible? Actual demo starts at 1:05 At 1:25 they get at least one fact wrong in their explanation: they say the bottles "compress and cool" the air. No. If you compress air, you raise its temp. At 1:45 they claim a measurable temp drop of 5 degrees. Discuss!