I bought a second hand Myford super 7 lathe recently and the item in the photo came with it. I have no idea what it is or what it would be used for. Presumably something for model engineering as the chap I bought the lathe from was into making model loco's.
Look up wishbone drill sharpening jig. It's for very small drills. There's a thread on this site but I don't know how to reference it. Perhaps someone could add a link please.