The article states that these tubes are not available commercially
but this is not correct.
DAGS for "cold air gun" if anyone's interested.

Art

"J T" wrote in message
...
http://www.visi.com/~darus/hilsch/index.html I would imagine it would
work, but not sure of the efficiency. If you had water, or wind, power
running a compressor, you could have it for "free". Interesting.

JOAT
When you're up to your ass in alligators, today is the first day of the
rest of your life.
- Archchancellor Mustrum Ridcully, UU