Only the letters of unmarried ladies and widows are addressed with their baptismal names. The letters of married ladies are addressed with their husbands' names, as "Mrs. John Smith." LETTERS OF INTRODUCTION. Letters of introduction should be brief and carefully worded. Give in full the name of the person introduced, the city or town he is from, intimating the mutual pleasure that you believe the acquaintance will confer, adding a few remarks concerning the one introduced, as circumstances seem to require. Modest persons sometimes shrink from delivering letters of introduction which appear to them to be undeservedly complimentary. Letters of introduction are left unsealed, to be sealed before delivery by the one introduced. They should receive immediate attention by the parties who receive them. When a gentleman delivers such a letter to a lady, he is at liberty to call upon her, sending her his card to ascertain whether she will receive him then, or appoint another hour that will be more convenient. The same rule is to be observed by those whose stay in the city is short. He may also send it to her with his card bearing his address. A letter of introduction should not be given, unless the person writing it is very well acquainted with the one whom he introduces, and the one to whom he writes. If the person who receives such a letter is really well-bred, you will hear from him or her within twenty-four hours, for a letter of introduction is said to be like a draft, it must be cashed at sight. The one receiving it either invites you to dine, or to meet others, or to a drive, or to visit some place of amusement. Too great caution cannot be exercised in giving a letter which makes such demands upon an acquaintance. When the letter of introduction is left with a card, if there is a gentleman in the family, he may call upon the stranger the next day, unless some engagement prevents, when he should send his card with an invitation. If the letter introduces a gentleman to a lady, she may write a note of invitation in answer, appointing a time for him to call. The following is an appropriate form for a letter of introduction. [Illustration] [Illustration: _New York, Dec 20, 1880._ _Dear Sir:_ _I take great pleasure in introducing to you my esteemed friend, Miss Ida A Thornton, a young lady of culture and refinement, who will spend a few months in your city. I am sure that an acquaintance with her will be a pleasure to you, as it will also be to Miss Thornton. Any favor you may show her during her stay in your city, I will consider a personal favor._ _Yours Sincerely,_ _Mrs. J.Q.A. Jones._ _To Geo. Morris,_ _Chicago._] The envelope containing a letter of introduction, should be addressed as follows: