Minstrel Piano

[Victor Belanger]

Hello everyone,

Is there anyone can shed some light on this particular instrument.

It is a portable piano, almost the size of a clavichord, with a cast 
iron plate, harpsichord tuning pins, hammers like a square grand. 
Ivory keys that are in good shape.
Rumors was that is was made by Knabe.
The case has two handles  made of brass.

Unfortunately there is no damper mechanism. On the plate itself, it 
has holes that are definite signs of where dampers go.
My question to you is has anyone seen this particular style of 
instrument and if so could someone explain how the damper mechanism 
work or was fabricated.
The client would like to have another mechanism installed.
I doubt that I can do that.
However if I can find one, or a diagram, that would be a good start.

Thanks.

Victor Belanger RPT
Somerville, MA