That's a compound off of a South Bend lathe that has been adapted to the Logan lathe.
First thing that has to come off to get the rest apart is the Acme threaded screw. To remove it, insert a Starrett pin punch in the blind hole just behind the graduated dial. It's right handed thread, so force it in a counter clockwise direction to break loose. Once it is loosen, rotate to remove. You will have to rotate the handle the other direction to advance the slide forward so it don't get in a bind. After removing the screw, next remove the set screw holding the nut in place. Then pry the nut out. Once done, the slide should come apart. Now, how it's connected to the other piece that adapts to the Logan, that's another story you'll have to figure out. Ken