Kepler?
It has a width axis, and maybe you saw a narrow instance?

Dunno, could be anything, almost. What else do you remember?
What was the "a" like? Maybe hypnosis would trigger some recollection. ;-)

hhp

Searching a bit, I found Zapf himself did Edison and also Marconi. Both show the influence of his earlier Melior. Could you have seen one of these?

I remember the curved characters (top of the a, the c, s, etc) had squared terminals, much like Verona. Thanks William for Edison, I was not aware of it, though it's not the face that I had in mind, but a valuable resource for this style.

Maybe 'RePublic', by Tom� Brousil / Suitcase Type Foundry.?
( Based on a original type design by Stanislav Mar�o )

http://www.suitcasetype.com/page.php?lmut=en&section=font&font=rePublic

( PDF Sample, 'RePublic' )