From The Essential Handbook of Victorian Etiquette, by Professor Thomas E. Hill

• Never point at another person.
• Never wantonly frighten others.
• Never make yourself the hero of your own story.
• Never pick your teeth or clean your nails in company.
• Never question a servant or a child about family matters.
• Never read letter which you may find addressed to others.
• Never call attention to the features or form of anyone present.
• Never seem to notice a scar, deformity, or defect of anyone present.