[ Ref. Steve Robbins in 150426 MMDigest

It sure looks like an Ampico vacuum pump.  As I understand it, the
reservoir on the right hand side was not always used.  (My Haines
Bros. Ampico upright does not have one -- maybe a cost-cutting move?)
Could that be a spill valve on the reservoir?

I have sometimes wondered whether American Piano Co. made these pumps
or bought them from an outside supplier.  In the latter case, similar
pumps would likely have been used elsewhere.

John Wolbach