To Take French Leave
The Emily Post of France in the eighteenth century ruled that a guest who had pressing engagement elsewhere might without propriety leave the function which he was attending without going through the formality of seeking his host or hostess and making a ceremonious apology for his departure. The latter, it felt, might lead to a general exodus of guests and be embarrassing to the host.
A Hog on Ice by Charles Earle Funk, 1948.
