The Round-up is a magazine story.
Whilst waiting at a signal, Thomas watches Ben the shepherd and his dog Jess round up the sheep. One day, Thomas passes the field again and Jess the dog barks at him. Thomas, who thinks something must be wrong, grinds to a halt. It turned out that Ben the shepherd had gone to rescue a lamb from a ditch only to fall in and get trapped himself. Thomas and his crew come to the rescue, and help Ben and the little lamb out of the ditch.