Raising Steam - (Discworld novel 40)

It's all change for Moist von Lipwig, swindler, conman, and (naturally) head of the Royal Bank and Post Office. A steaming, clanging new invention, driven by Dick Simnel, the man with t'flat cap and t'sliding rule, is drawing astonished crowds - including a few particularly keen young men armed with notepads and very sensible rainwear.