14 January

This is a vortex tube. A miraculous thing hidden in industrial sheds. Compressed air enters the chamber (the bit with EXAIR written on it), and forms a vortex; like a mini-tornado. That vortex separates the air into two separate streams, one hot, and one cold (red and blue in the picture). The cold stream can get to cryogenic temperatures, minus 50 degrees C or lower, and the hot stream can go well over 100 degrees Celsius. The vortex was the centre of ancient knowledge, the link between the sciences and humanities. This device challenges everything we think we know - modern ideas can’t explain how it works. Our education and our interests are now so narrow, that this miracle goes unnoticed.