Working Knowledge: Big Air; July 2004; Scientific American Magazine; by Mark Fischetti; 2 Page(s)

Pipe organs are the largest, most powerful musical instruments on earth. Yet a mere sliver of wood stands between a thundering roar and dead silence.

Organs have functioned on the same simple physics since they were first constructed around 250 B.C. Air flows from a reservoir up past leather-covered wooden pallets into pipes of various lengths, vibrating to produce different pitches. For 2,000 years, humans - usually boys from a church congregation - squeezed bellows by hand or feet to supply the air, until electric motors and blowers took over.