Ghost 15 purging old image incremental with no history

The backup destination tab is telling me there are no backups.   I assume that is because there is no history.   What I am trying to do is to cleanup old backups and consolidate to a fewer number.   Since there aren't any from Norton's view, how do you do this?

 

I can actually explore the backups but I don't know how to safely clean up the disk.