What type of wrench is this?

[GaryD]

I picked up several of these old wrenches at a yard sale.  Seems like I should know what the little pin is, but can't remember. (Top right in picture.)  Did this type of wrench have a specific use?

[mrchuck]

Don't know. I have several much larger wrenches with a larger pin on them, like a hammer actually.
Posted here, know one knew.