by Carl P.
Flexible plastic tube, board with holes, nuts,
washers and screws.
Place three pegs (nuts, screws, washers) into
certain holes in the board until your tube fits. (See arrows
at left.) Then wrap wire around the tube and the board at
the other end. Pour water into the free end of the
How to make the sound:
Beat on the end of it with your hand. It vibrates
the air column inside the tube.
You can change the pitch by raising and lowering the
tube to change the size of the air column. You can beat
harder or softer on the tube to change the