Please identify this tool

[chipsndust]

This is not one of those posts where I know the answer and you have to guess!
I really don't know what this thing is, and I'm hoping someone can tell me.

It was in a box of metal and woodworking tools that my wife brought home from an auction. I got a few nice old tools out of it and this thing was among the stuff I saved. It's made of solid brass, and looks like some kind of measuring gauge. No markings on it that I can see.

Anybody know what it is?

 

[dex3361]

Its a depth gauge.

 

[dave1949]

Some sort of home-made depth gauge for a timber framer making joints?