A – tool post holder
B – spindle
C – spindle
D – clamp
E – hole attachment (see-saw device to translate movement from one end to the other where the dial indicator can read
F – snug
G – buttons for end of dial indicator plunger
H – back plunger dial indicator
I – internal threaded knurled nut, for extending indicator plunger? No, I think it is an incomplete “shock absorbing anvil”
Update: “Oldfussbudget” lived up to his name by commenting how it would be nice to see the tool in action. So here are a series of pics with the dial indicator mounted on my lathe in 3 set ups.
First up is the tool post holder (A) in my old lantern style tool post. Spindle B is screwed into one of the threaded holes in the bar, the snug (F) attached, and the dial indicator held by same snug. A button has been screwed into the plunger of the dial indicator and is resting on the work piece. The bezel of the dial indicator moves to allow zeroing of the gauge. This set up can be used to check the runout of the work piece, especially useful when trying to center round stock in a 4 jaw chuck (3 jaw chuck shown in pic).
Now the see-saw, hole attachment (E) has been added to the set up and you can see how it can be used to check the run out in an internal surface.
Another view of same.
Better shot, showing button on plunger
And using the clamp (D) a spindle (C) to hold the gubbins onto an old style lathe tool holder mounted in the old style tool post.
And to answer Oldfussbudget’s other request, the only serial number found was on the dial indicator itself. The box had nothing. Oh, and you can still buy this dial indicator.