Letters are written in the third person in answer to formal invitations so worded, and in correspondence between people but slightly acquainted or known to each other only by reputation, persons not social equals, and by tradespeople and their patrons.
Great care should be taken to preserve the impersonal diction throughout the letter, and to refrain from signing it. The tone should always be formal and very polite.
An order may take the form of a request, as "Will Mr. Sutherland please . . . and oblige," with the signature of the writer.
Informal Invitations and Announcements
In inviting a friend to visit you, it is customary to mention the length of the visit, setting a definite date for it and limit to it. This makes it possible for both hostess and guest to arrange other engagements.
A time-table of the trains, if the guest comes from the distance, with an account of the trolley lines, if from near at hand, should be enclosed.
The engagement of a daughter may be announced by informal notes to one's whole circle of friends and acquaintances. The following form of note may serve as a suggestion: "I am sure that you will join our household in sympathy with Eleanor in her happiness when I tell you that she has just announced her engagement to Mr. Harold Farnham, a man of whom her father and I thoroughly approve. The wedding will not take place for some months, but felicitations are in order."
Letters of Condolence
A letter of condolence should be short and quite sincere, or else the courteous custom of sending it is more honored in the breach than in the observance.
Such letters should be sent very promptly.