> Maxwell's demon -> WiebelRohr / Hilsch tube / > Ranque-Hilsch / Vortex tube http://www.instructables.com/id/The-Hilsch-vortex-tube/?ALLSTEPS Unfortunately I have everything needed =3D> temptation --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .