From A Murder of Quality:

He enjoyed the bus. The conductor was a very surly man with a great deal to say about the bus company, and why it lost money. Gently encouraged by Smiley, he expanded wonderfully so that by the time they arrived at Sturminster he had transformed the Directors of the Dorset and General Traction Company in to a herd of Gadarene swine charging into the abyss of voluntary bankruptcy.