New yearsing in St Lucia—home to perhaps the world's only drive-in volcano—I came across the French etiquette guide, Rules of Civility and Decent Behaviour In Company and Conversation, that President Washington translated into English when he was but a schoolboy.
When in Company, put not your hands to any part of the body not usually discovered.
Eat not in the streets, nor in your house, out of season.
Kill no vermin, fleas, lice, ticks, et cetera in the sight of others; if you see any filth or thick spittle put your foot dexterously upon it; if it be upon the clothes of your companions, put it off privately, and if it be upon your own clothes, return thanks to him who puts it off.
If you cough, sneeze, sigh, or yawn, do it not loud but privately, and speak not in your yawning, but put your handkerchief or hand before your face and turn aside.
The gestures of the body must be suited to the discourse you are upon.