looks like a lever-action hole cutter of some sort.
appears to have about a 1" diamond-point bit. For going through bark, etc.
to install a sap tap on a sugar maple?
If I was in a facituous mood, I'd suggest it was for _miniture_ golf greens.
"Fisher Controls" is still in Marhalltown, Iowa. Drop them a line.
They're a big player in electical/pneumatic/hydraulic control systems
It's probably associated with a medium-to-high pressure steam system.
Possibly some sort of over-pressure relief valve.
Possibly a pressure-transformer.
Probably "something else". <grin>
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