Toby and the Stout Gentleman - S1-E21
Revealing mistake: When Toby and Sir Topham Hatt are at Lower Arlesdale, Toby's face is loose.
Toby and the Stout Gentleman - S1-E21
Other mistake: Toby passes the Post Windmill twice, but that is on Thomas' branch line.
Toby and the Stout Gentleman - S1-E21
Revealing mistake: In a close up of Sir Topham Hatt, the camera shakes.
Toby and the Stout Gentleman - S1-E21
Revealing mistake: The water is not flowing when Toby passes Arlesdale Lake.
Answer: He was in the water.