Ben's Blunder is a magazine story.
Ben is busily working at the Quarry when Diesel rattles up alongside him. He tells Ben that he has an important message; the Fat Controller wants a load of rock delivered to his garden right away. Ben is puzzled as Diesel rumbles away; why would the Fat Controller want a load of rocks. Ben thinks that Diesel must be trying to trick him and decides to take no notice of Diesel's message.
The next day, the Fat Controller arrives and asks Ben why he has not delivered the rocks yet. Ben blushes bright red as he realises that Diesel's message had been genuine after all. Ben explains that he thought it was a trick and the Fat Controller tells him that he wants the rocks to build a rockery for his wife's birthday. Ben promises the Fat Controller that he will deliver the rocks immediately.
- Bill is strangely absent for unknown reasons.