I have tried searching on this but can't seem to find my answer. I'm looking at picking up a clock. The person selling it is not sure if it's 30 hour or 8 day (the clock needs some help). It's spring wound, not chain driven. I thought there was a way of looking at the going train and determining if it's a 30 hour or 8 day movement. Here is a picture of the movement: How do I tell? Thanks!