While in Seattle last week, I picked up an Audubon Bird Call—an ingeniously-designed American classic. It was invented by Roger W. Eddy in 1952* and consist of 4 parts: a hollow birchwood dowel, a pewter handle that is loosely held in place with an opposing screw and a little bit of rosin on the inside. To use it, you just twist the dowel lightly. Simple design, simple construction and simple to use.
* Nation’s Business, August 1984