I am in the process of purchasing a 1920 Seeburg Style L.  The case
shows that there was once a pneumatic switch on the back side of the
left front of the upper case.  I can see in vintage Style L photos that
there seems to be a knob with a label over it.

The knob and label are missing on this Seeburg.  However, the pneumatic
switch inside the cabinet appears to be intact and is tubed to a series
of pneumatic switches under the stack.  I suspect this may have been an
cut-out for the mandolin.  However, in moving this switch to what looks
to be "on" or "off" positions, nothing happens.

My question is, What is this switch for, if it is not a cut-out for the
mandolin?

Tom DeLay
Salinas, Calif.