Character mistake: In the scene in front of the Western Wall in Jerusalem Poirot says "In the Church of the Holy Sepulchre above us..." but the church isn't located there. It's northwest from there, in the Christian Quarter of the Old City. (00:04:10)
Character mistake: Poirot identifies Prof. Hardman's revolver as a 1927 police-issue weapon due to its blued finish and chequered grips. In fact, these features were common in the widely-available civilian versions of the Colt 'Police Positive' revolver and not the least bit specific to police-issue weapons.
Answer: Dickens used satire, irony, and humor as a means to express social criticism and political commentary. His novels were filled with comical characters and colorful dialogue. He used a humorous writing style to expose the Industrial Revolution's harsh and negative impacts like poor education, worker exploitation, social inequality, and other societal ills such as extreme poverty, domestic violence, alcoholism, and so on. Poirot is obviously responding to that.
raywest ★