Thankyou to all those who have responded to my first call on this subject.
Just to clarify what we are looking for - it is precisely those short
vaudeville segments in an otherwise all-film programme that we are
interested in (like those described by Cal Pryluck). In Australia, some
cinemas used these live prologues and interludes throughout the twenties
and even into the early thirties.  The suggestions so far have been really
helful, and thankyou to everyone who posted. Maybe this explanation might
even bring some more...
 
Ina Bertrand