> Rubber became useful after the invention of the vulcanisation
> process by Mr. Goodyear in 1939.  Before that all bellows were
> made from leather.

The date mentioned as 1939 is clearly wrong.  I have an early
1887 Victolian 46-note organ, made by American Orguinette Company,
pre-Aeolian, which still plays on it's original rubber cloth
(patched at the corners).

Kevin McElhone, Northants, UK