Ballast is the third episode of the sixth season.
Railway Series Book
Small Railway Engines
New ballast is being laid in the track bed. Donald and Douglas bring it from a line that starts at Tidmouth, and all they will say is "verra wee engines" bring it down from the hills. Duck is curious and asks to take some trucks along the line. There, he meets a small green engine called Rex, who tells him about the "chute" that loads his trucks. The next time Duck visits, Rex introduces him to two other engines, Bert and Mike. When Duck discovers that they don't have any passengers yet, he leaves, promising to bring some for them.
- Donald and Douglas
- Henry (does not speak)
- James (does not speak)
- Thomas (cameo)
- Percy (cameo)
- Sir Topham Hatt (mentioned)
- The Small Controller (mentioned)
- Stock footage from Gordon Proves his Point is used.