So what were these anyway?

They are Mason's goggles (as in the Free Masons). 

Apparently, you were not allowed to know the identity of the other masons until you were a full member of their Secret Society. So they blind-folded you with these until you were made a member.

History is weird and fun. (I say history, but the Masons are still around, I'm not sure if they still use these though).

I plan on fixing the broken strap and maybe putting in some lenses (with friction, I don't actually want to mod an antique) and using them for Steampunk costumes.