18 April 2012
When Gay-Lussac and von Humboldt wanted to import some thin-walled test tubes from Germany, they asked the manufacturer to seal the end of the tubes and send them to Paris labelled "German Air". The French customs men could not find any duty rate for air in their manual, and let the tubes in free. -- Chasing the Molecule by John Buckingham
So, science is indeed useful sometimes.
German Air • Opuss № I