While studying physics at UCLA (about 1960) and spending every lunch
hour in the music library researching pipe organs, I ran across a
statement that Helmholtz built cardboard pipes for use in his studies
of sound.  As I remember it he was attempting to show that the pipe
material didn't matter much (probably only small pipes).  Can anyone
shed any light on this?

As an experiment I built four pipes from 8-1/2- x 11-inch manila
folders (thin, stiff cardboard), patterned after the 1-foot open flue
pipes from my Robert-Morton theatre organ.  I could not tell any
difference, but I never tried anything larger.  It was never my intent
to use them.  My kids loved them, while they lasted.

I visited a local commercial organ builder and saw bass pipes built as
a unit: four pipes between 4 foot by 8 foot sheets of 3/4 inch plywood,
with common interior walls.  I often wondered if it would be possible
to make one foot and smaller pipes by injection molding, as a single
unit.

John Spradley

 [ Hermann Ludwig Ferdinand von Helmholtz (1821-1894), German
 [ scientist whose contributions in physiology, optics, acoustics and
 [ electrodynamics greatly advanced 19th-century scientific thought.
 [ (From http://encarta.msn.com/ )  -- Robbie