B. G. Jefferis and J. L. Nichols

“ Cultivate paradoxes in conversation with your peers. They add interest to common-place matters. To strike the harmless faith of ordinary people in any public idol is waste, but such a movement with those able to reply is better.
Never discourse upon your ailments.
Never use words of the meaning or pronunciation of which you are uncertain.
Avoid discussing your own or other people's domestic concerns.
Never prompt a slow speaker, as if you had all the ability. In conversing with a foreigner who may be learning our language, it is excusable to help him in some delicate way. ”

“ Do not be too lavish in your praise of various members of your own family when speaking to strangers; the person to whom you are speaking may know some faults that you do not.
Do not feel it incumbent upon yourself to carry your point in conversation. Should the person with whom you are conversing feel the same, your talk may lead into violent argument. ”

“ Do not whisper in company; do not engage in private conversation; do not speak a foreign language which the general company present may not understand, unless it is understood that the foreigner is unable to speak your own language. ”