This section is from the book "Hill's Manual Of Social And Business Forms: A Guide To Correct Writing", by Thos. E. Hill. Also available from Amazon: Hill's Manual Of Social And Business Forms: The How-To-Do-Everything Book Of Victorian America.
Should dancing form a principal feature of the entertainment, and the piano be used to furnish music, the hostess or one of the family should play the instrument. One of the guests should not be depended upon to furnish all of the music. If the hostess cannot play, a pianist for the occasion should be engaged. Either a lady or gentleman-guest may with propriety volunteer to play, if they choose; but the hostess cannot expect that music, thus voluntarily offered, will be cheerfully furnished for more than one dance.
It is courtesy, while anyone is playing an instrument, or singing, to preserve as much stillness as possible. Should you converse, do it so quietly as not to be heard by those near the piano. Should your conversation be animated, it is well to retire to another room.
Amateur performers upon the piano should thoroughly commit to memory a few pieces to play independently of notes, as to take sheet-music to a party is a hint that they expect to be invited to play. If possible, have the voice in good condition also, so as not to be obliged to complain of a cold. To eat a small amount of horse-radish just previous to reading, singing or speaking, will quite effectually remove hoarseness.
Any lady-guest being invited to play the piano, it is courtesy for the gentleman nearest her to offer his arm and escort her to the instrument. While she is playing he will hold her bouquet, fan and gloves, and should also turn the leaves if he can readily read music, but he should not attempt it otherwise.
When a guest is invited by another guest to play the piano, it will be well to wait until the request is seconded by others; and even then the guest may not play unless it should meet the favor of the hostess, and it is believed to be the pleasure of the majority of the company. If certain that the playing will be acceptable, it is well to suggest to the hostess to invite your friend.
It is very impolite to speak disparagingly of the piano, however much it may be out of tune, or however inferior it may be. More especially is it a breach of etiquette to draw unfavorable comparisons between the instrument and another elsewhere.