Sharpe's Justice

When the innkeeper Arnold asks 'which one' of the 'King Georges' is meant by Harper, this is a reference to the situation in England at the time: King George III. ('the mad one') was already certifiably insane, but still officially king; while his son ('the fat one', later to become George IV.) reigned in his stead as the Prince Regent.

The "new steam engine" intercepted during transport by the bad guys is in fact technically a boiler, not an engine.