|Portrait of an Unknown Daguerrotypist, 1845|
J. Paul Getty Museum, Los Angeles
"Photographs should never be solicited from a mere acquaintance. Wait till you know a lady well before asking for her likeness. No gentleman should be allowed to possess, nor should he seek to possess, a lady's picture without first having met her at least seven times... And it is also unnecessary to comply with a like request from the lady till of fast acquaintance."
Mortimer Delano de Lannoy, Simplex Munditiis. Gentlemen (1891)
Best practices for dating: Keep plenty of headshots on hand, but never hand them over before the seventh date.