Looks like a small switch set... like for routing calls...
Update: I found this: A 1937 text states: "The Dictograph is frequently used, particularly in large organizations where a supplementary inter-communicating system which provides direct connection between a relatively small number of individuals, often officers and chief executives, is desired. The receiver and mouthpiece are similar in appearance to the hand telephone. Connection is made by the person calling simply by depressing a small key, which is marked to indicate a particular individual."
Mojjax, it mystifies me how many unusual items you come up with.
Very nice item, I've never seen one... there can't be many of those left! $
Good info as always Jim.
Mojjax, unscrew the mouth or ear piece on the handset... there should be date codes on those.
Beth, I think this deviates from the units on your links, in that the handset seems to have have been an original part of the piece, unlike the handsets on the eavesdropping machines. As always - I can be wrong.
It's a small PBX switchboard. We had one at McCoy AFB in the command post in the 1960s. About Korean War era I think, or at least ours was. We could switch or patch calls from one line or several. It was soon replaced by a digital push button phone before they were available to the general public. When I was stationed on a bombing range in Libya, we still used the old crank up phones. The military always had the oldest obsolete equipment but when they upgraded they went high tech. for the times. Monty