Big ol' level.

[copperhead]

This, like the straight edge in a previous post, was my bosses grandfathers too. It's approx 6 1/2 ft long. All the vials at still intact. Haven't tested them for accuracy though..lol

There is a faint stamped marking on it, but I haven't been able to decipher yet. It's surprising light for it's size. Not sure what type of wood it's made out of. 

[Aunt Phil]

Plaster hanger's level for wall & ceiling work