According to R.H. :

212) Hmmm ... can you measure the distance between the sides and the
top and bottom surfaces? It looks as though it is intended to
be a gauge block with a handle of some sort.

Is it tapered, or is that an artifact of the camera?

It's not tapered, though it does look like it is in the photo.

I would guess that it is quite close to 1.000" square.

Just measured this tool, it's 15/16" square, you're probably right about it
being a gauge, I couldn't find any similar ones to verify it, so I included
it in the unsolved set.

O.K. How precisely is it 15/16"? Do you have a micrometer to
measure it precisely? I would expect it to be pretty precise, as it
looks to be surface ground to dimension.

Are there any markings on it other than the end markings?

Enjoy,
DoN.

--
Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---