Not sure but looks like a map makes tool

[Mark1985]

I found this today it has tick marks on it and still some wood in it any idea if that had them on the civil war found it next to these

 

[NOLA_Ken]

Definitely part of a folding ruler. Not sure about the age though.

 

[recondigger]

Definitely part of a folding ruler. Not sure about the age though.

You beat me to it that is for sure what it is

 

[clovis97]

Yes, it is a hinge from a folding rule.