M aker
P.O.K.E.R. Night
Or, Let’s Build a Vortex Tube Party!
By Mister Jalopy
IN 1867, SCOTTISH PHYSICIST ROBERT
Clerk Maxwell proposed a “thought experiment,”
suggesting that it may be possible to break the
second law of thermodynamics, if you could find
a molecularly minded demon that was willing to
cooperate.
Start with two hypothetical containers of equal
temperature with a connecting trap door controlled
by a gatekeeper to sort hot from cold molecules.
When the demon sees a fast/hot molecule racing
toward the door, he opens the trap to let the hotter
molecule speed into container A. Similarly, if a slow-moving molecule is headed toward container B, the
demon would allow it to pass until the two containers are at different temperatures. Assuming that
the demon would have modest demands for his
efforts, you would break the cornerstone of physics
laws — something for nothing.
The Hilsch Vortex Tube
After an impressive 72-year run, the “Amateur
Scientist” column fell victim to a 2001 Scientific
American modernization effort. A terrible loss, the
“Amateur Scientist” was an inspirational resource
that dedicated considerable effort to explaining the
hard science behind the projects.
Whether working on “Cloud Chambers to Detect
Nuclear Events” (see page 156 for MAKE’s version
of the cloud chamber ) or “An Inexpensive X-Ray
Machine,” you really felt like you were in the midst
Photography by Mark Frauenfelder and Mister Jalopy
34 Make: Volume 09
